Missile Defense Options for Japan, South Korea, and Taiwan: A Review of the Defense Department Report to Congress

Missile Defense Options for Japan, South Korea, and Taiwan: A Review of the Defense Department Report to Congress

Order Code RL30379
Missile Defense Options for Japan,
South Korea, and Taiwan: A Review of the
Defense Department Report to Congress
November 30, 1999
name redacted
Specialist in U.S. Foreign Policy
name redacted
Specialist in National Security Policy
name redacted
Research Associate
Foreign Affairs, Defense, and Trade Division

ABSTRACT
This report reviews the unclassified 1999 Department of Defense (DoD) report to Congress
on U.S. theater missile defense systems that could protect, and could be transferred to,
Japan, South Korea, and Taiwan. It summarizes the DoD report and, for clarification, some
of its unstated assumptions. It further analyzes policy implications of the report’s findings
and assumptions, and outlines U.S. options for missile defense in East Asia. Because the
DoD report is unclassified, written on a tight time deadline, and limited in scope, it does not
address certain key issues that are raised and discussed here. The ability of these systems
to defend against all missile threats remains questionable, and it is not clear what would be
required to link three separate systems for Japan, South Korea, and Taiwan into a regional
system. DoD was not asked to address political, strategic, or economic issues, but this CRS
Report identifies several such issues that emerge as possible topics for further congressional
examination. For more information on related legislation, see CRS Issue Brief IB98028,
Theater Ballistic Missile Defense. This CRS Report will not be updated.

Missile Defense Options for Japan, South Korea, and
Taiwan: A Review of the
Defense Department Report to Congress
Summary
The FY 1999 National Defense Authorization Act (P.L. 105-261) required the
Secretary of Defense to study the U.S. missile defense systems that could protect, and
could be transferred to, Japan, South Korea, and Taiwan. The Secretary was directed
to describe these missile defense systems and the factors used in the study in separate
classified and unclassified reports to Congress. In May 1999, the Department of
Defense (DoD) transmitted the unclassified report which provides a discussion of
five missile defense systems that are currently being developed by the United States
and could be provided to Japan, the Republic of Korea, and Taiwan: systems similar
to the U.S. Patriot PAC-3, Navy Area Defense (NAD), Theater High Altitude Area
Defense (THAAD), and Navy Theater Wide (NTW) Phase I with Standard Missile-3
Block I, and Phase II with Standard Missile-3 Block II. The report weighed various
combinations of these systems, stating what number of missile defense units “could
reasonably be expected to provide area coverage ... against a limited attack....”
DoD’s analysis of the individual characteristics and limitations of the five systems
showed they would provide different results for different areas. For Japan, an option
like NTW Block II proved best. The differing geography of South Korea and the
threat it faces indicated a combination of THAAD-like and PAC-3-like systems
would be most effective. According to the DoD report, Taiwan could be protected
by one system similar to THAAD, NTW Block I, or NTW Block II. However,
Taiwan’s defense may well require a combination of lower-tier systems like PAC-3
or NAD and upper-tier systems like NTW (Block I or II) or THAAD for layered
defenses.
Information in the DoD report was constrained because it was unclassified, the
reporting requirement was narrow, and DoD had relatively little time to complete the
study. The DoD report focuses on the TMD requirements for coverage of particular
areas, considering the minimum number of firing units needed for maximum
coverage. It therefore remains unclear how well these U.S. TMD systems would
protect East Asia against the missiles of North Korea and China. For instance, the
report does not explain the net capabilities of the defense systems against fast
missiles, low-flying missiles, a large number of missiles, missiles carrying weapons
of mass destruction (WMD), or missiles with penetration aids, multiple warheads,
or submunitions. Some of these issues relate to the different perspectives among
foreign leaders, as well as U.S. citizens, as to the technical distinctions between
strategic missiles and theater missiles, and between national missile defense and
theater missile defense. It was also beyond the scope of report requirements to
evaluate the international political, strategic and tactical military, or foreign and
domestic economic advisability of transferring particular missile defense units to
Japan, South Korea, or Taiwan. In a context broader than that presented by the DoD
report, there are issues and options concerning alternative ways in which the United
States could provide missile defense to East Asia. For instance, it could unilaterally
deploy TMD systems with U.S. troops in Asia; sell TMD systems to one or more
parties; or co-develop and co-produce TMD or NMD systems with one or more allies
or friends.

Contents
Overview of the Department of Defense Report . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Legislative Requirement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Summary of the DoD Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Analysis of the DoD Report and Issues
Beyond Its Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
TMD System Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
What Are Limited Ballistic Missile Attacks? . . . . . . . . . . . . . . . . . . . . . . . . 3
Key Issues Regarding the Threat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
The Ballistic Missile Threat and Asian Counter Forces . . . . . . . . . . . . . . . . 5
Capabilities and Limitations of U.S. TMD Systems . . . . . . . . . . . . . . . . . . . 7
Three TMD Systems Versus a Regional Missile Defense System . . . . . . . . 9
U.S. Missile Defense Systems That Were Not Evaluated
. . . . . . . . . . . . . 10
How Are the Examples Different From U.S. TMD Systems? . . . . . . . . . . . 11
How Would U.S.-Deployed TMD Contribute to Asian Defense? . . . . . . . . 11
What Territory Would Be Considered Protected? . . . . . . . . . . . . . . . . . . . . 11
How Would TMD Affect the Regional Military Balance? . . . . . . . . . . . . . 11
How Do TMD Options Suggested Compare to Other Options? . . . . . . . . . 12
Assessment of DoD Report for Japan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
The Missile Threats to Japan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Potential Capabilities and Limitations of TMD Systems . . . . . . . . . . . . . . . 15
Japanese Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Assessment of DoD Report for Republic of Korea . . . . . . . . . . . . . . . . . . . . . . . 18
Missile Threat to the Republic of Korea . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Potential Capabilities and Limitations of TMD Systems . . . . . . . . . . . . . . . 18
Republic of Korea Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Assessment of DoD Report for Taiwan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Missile Threats to Taiwan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Scale of Attacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Scope of Threat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Wide Range of Possible Threats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Potential Capabilities and Limitations of TMD Systems . . . . . . . . . . . . . . . 24
Taiwan’s Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
DoD Report’s Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Alternative Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Limits to Missile Defense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Political Considerations and U.S. Options . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Arguments Against . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Arguments in Favor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
U.S. Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
U.S. Considerations in Cooperative Missile Defense Programs . . . . . . . . . . . . . 29
U.S. Options for Missile Defense in East Asia . . . . . . . . . . . . . . . . . . . . . . . . . . 31

List of Tables
Table 1. “Threat Missile” Inventory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Table 2. Other Missiles in the Region . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
This analysis was originally prepared at the request of the Honorable Frank H.
Murkowski, and is being reprinted by CRS for general congressional distribution
with his permission.

Missile Defense Options for Japan, South
Korea, and Taiwan: A Review of the
Defense Department Report to Congress
Overview of the Department of Defense Report
Legislative Requirement
The FY 1999 National Defense Authorization Act1 required the Secretary of
Defense to study the U.S. theater missile defense systems that could protect, and
could be transferred to, Japan, South Korea, and Taiwan. The Secretary was directed
to describe these missile defense systems and the factors used in the study in separate
classified and unclassified reports to Congress. In February 1999, Congress received
the classified report, and in May it received the unclassified2 report. The following
Congressional Research Service report reviews the Department of Defense (DoD)
unclassified report to Congress, summarizing key information and unstated
assumptions upon which the report is based, analyzing policy implications, and
outlining U.S. options for missile defense cooperation in East Asia.
The text of the legislative reporting requirement follows:
SEC. 1533. REPORT ON REQUIREMENTS FOR RESPONSE TO
INCREASED MISSILE THREAT IN ASIA-PACIFIC REGION.
(a) Study.--The Secretary of Defense shall carry out a study of the architecture
requirements for the establishment and operation of a theater ballistic missile defense
system in the Asia-Pacific region that would have the capability to protect key
regional allies of the United States.
(b) Report.--(1) Not later than January 1, 1999, the Secretary shall submit to the
Committee on National Security of the House of Representatives and the Committee
on Armed Services of the Senate a report containing--
(A) the results of the study conducted under subsection (a);
(B) the factors used to obtain such results; and
(C) a description of any United States missile defense system currently deployed
or under development that could be transferred to key allies of the United States in
the Asia-Pacific region to provide for their self-defense against limited ballistic
missile attacks.
(2) The report shall be submitted in both classified and unclassified form.
1 P.L. 105-261, H.R. 3616, signed into law on October 17, 1998.
2 U.S. Department of Defense. Report to Congress on Theater Missile Defense Architecture
Options for the Asia-Pacific Region, May 1999, 15 pp. (The unclassified report.)

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In addition, the conference report on H.R. 3616 (H.Rept. 105-736) said for the
purposes of this requirement, the term “key regional allies” refers to Japan, the
Republic of Korea, and Taiwan.
Summary of the DoD Report
The unclassified DoD report provides a discussion of five missile defense
systems that are currently being developed by the United States and could be
provided to Japan, the Republic of Korea, and Taiwan: systems similar to the U.S.
Patriot PAC-3, Navy Area Defense (NAD), Theater High Altitude Area Defense
(THAAD), and Navy Theater Wide (NTW) Phase I with Standard Missile-3 Block
I, and Phase II with Standard Missile-3 Block II. For Japan, South Korea, and
Taiwan, the report lists a number of options, with each option stating what number
of missile defense units of which type “could reasonably be expected to provide area
coverage for each defended area against a limited attack by the different types of
TBMs likely to be arrayed against it.”3 In describing their technical methodology, the
authors of the report state:
The report quantifies the architecture force structure needed to provide
coverage against specific theater ballistic missile threats to most of the
territories for Japan, South Korea, and Taiwan. This defense also provides
protection of the critical assets identified by the U.S. intelligence
community.4
The report stressed that potential recipients would also need a source of early
warning such as “a combination of overhead surveillance and long range phased
array early warning radars,” and a communication system.
To determine the number of TMD units needed by each country, DoD used the
following methodology:
! chose potential launch sites of various types of theater ballistic
missiles
! overlaid a grid on the map of each defended territory
! estimated the required TMD systems and deployed them on the map
! portrayed the ability of threatening missiles to strike each grid of
defended territory
! determined if deployed TMD systems could intercept missiles and
protect grids
! repeated the process to achieve the greatest defended area with
fewest TMD units.
3 Report, p. 5.
4 Ibid.

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Department of Defense officials point out that:
! the options discussed in the report are “illustrative architectures
based on each country’s unique political and threat environment,”
! the report “is not intended to be a comprehensive analysis of TMD
in the region,”
! the report “does not suggest or imply a region-wide architecture
network,”
! the report “does not advocate/recommend deployment of any
specific TMD architecture.”
! “Because the focus of this study is possible TMD architecture, it
does not address their feasibility or desirability from political,
economic, or other security perspectives.”5
Analysis of the DoD Report and Issues
Beyond Its Scope
The following sections analyze and discuss the general approach and
assumptions of the DoD report and particular aspects of the report that apply to
Japan, the Republic of Korea, and Taiwan. In the process, this paper raises some
issues important to Asian missile defense that were considered to be beyond the
scope of the DoD report. This paper will then discuss TMD options for each of the
three potential recipients, discuss implications of the DoD findings, review additional
issues for U.S. cooperation in regional TMD, and list options that are available to
the United States.
TMD System Requirements
The DoD report provides a useful analysis of the types and numbers of TMD
systems that would be required to cover the areas of Japan, South Korea, and Taiwan.
It demonstrates that the unique geographic characteristics of the three and the threats
posed against them lead to different TMD requirements. It also points out some of
the limitations of the TMD systems that were considered. The limited nature of the
reporting requirement, the short time allowed, the security classification of specific
characteristics and capabilities of the TMD systems, the political sensitivity of
regional missile defense cooperation, and other factors prevented DoD from
discussing some other related issues.
What Are Limited Ballistic Missile Attacks?
The term “limited ballistic missile attacks” is ambiguous as to the nature and
scope of the limitations. In the debate on national missile defense, the term is used
with reference to unauthorized or accidental attacks by a major power, or attacks of
the type and scale considered possible for new missile powers. Such attacks would
5 The Report and, Theater Missile Defense (TMD) and East Asia TMD, Briefing for
Congressional Research Service, Ballistic Missile Defense Organization, March 18, 1999.

CRS-4
presumably consist of fewer than 200 warheads and might not include sophisticated
penetration aids.
The DoD report does not use this meaning of the term but considers limited
missile attacks against Japan, South Korea, and Taiwan to be attacks by a few (less
than five) missiles with ranges and speeds less than those of ICBMs (i.e., with ranges
and speeds of tactical or theater ballistic missiles).6 The DoD report considers theater
ballistic missiles to be those with ranges less than 3,500 km (2,170 mi). For this
report, DoD also limits the threat to missiles with conventional warheads – not
nuclear, biological, or chemical. Conventional warheads are often much larger and
heavier than warheads designed to deliver weapons of mass destruction (WMD). If
the Defense Department had included missiles armed with nuclear warheads, for
instance, some missiles would have had longer ranges and faster speeds and would
have been more difficult to intercept with a TMD system.
The report also does not consider missiles with penetration aids,
countermeasures, or altered trajectories, all of which would have decreased the
effectiveness of the TMD options presented. There are clearly benefits, but also
risks, of designing a system to defend against such a limited ballistic missile attack
but not against a more robust attack. Some analysts consider this limited threat more
plausible than some more sophisticated options. (The nature of the threat is
discussed further in the country sections of this report.) The extent to which the
attack is limited is key to findings of effectiveness of the missile defenses considered,
so it is important for all policy makers to agree on the meaning of the term “limited
ballistic missile attacks.”
Key Issues Regarding the Threat. Several aspects of the future missile
threat have received only limited attention in public reporting, and the DoD report
does fill these gaps:
! What types of missiles, with what characteristics, are likely to
threaten Japan, South Korea, and Taiwan in the year 2008?
! How many missiles might be launched against Japan, South Korea,
or Taiwan simultaneously? At what rate will potentially hostile
countries be able to launch missiles and how long are they likely to
be able to sustain missile attacks? These factors are important
because missile defense systems are limited on the number of
hostile missiles they can engage at once and over time.
! Will the missile systems of potentially hostile countries have
penetration aids, such as chaff, decoys, infrared emitters, jamming
equipment, multiple reentry vehicles, or submunitions?
! What warheads will the hostile missiles likely deliver?
! Could North Korea use IRBMs and ICBMs on a high (lofted)
trajectory against South Korea or Japan in order to achieve higher
speed reentry, or on a fast and low trajectory, that TMD systems may
not be able to intercept?
6 BMDO interview.

CRS-5
! Will North Korea be able to produce reentry vehicles and warheads
that can withstand the forces and temperatures of high-speed reentry
or extensive flight within the atmosphere? What testing would
North Korea require to have confidence in such reentry vehicles or
warheads?
! How effective will allied missile forces and other forces be in
deterring missile attacks?
The Ballistic Missile Threat and Asian Counter Forces
The table below shows the ballistic missiles of North Korea and China that DoD
considered to be potential threats in the analysis of TMD requirements for Japan,
South Korea, and Taiwan. These North Korean and Chinese short range ballistic
missiles (SRBMs) and medium range ballistic missiles (MRBMs) are limited in the
ways discussed in the previous section.7
Table 1. “Threat Missile” Inventory
Type
Range (km)
Payload (kg)
Status
NORTH KOREA
Scud-B variant
SRBM
300
1,000
In Service
Scud-C
SRBM
500
700
In Service
Nodong
MRBM
1,000-1300
1,000
In Service
Taep’o-dong-1
MRBM
1,500- 2,000
1,000
Tested with
Two stage
solid fuel third
stage on 8/31/98
CHINA
CSS-5
MRBM
1,800
?
In Service
(DF-21)
Conventional
CSS-6
SRBM
600
500
In Service
(DF-15/M-9)
CSS-7
SRBM
300
500
?
(DF-11/M-11)
CSS-8
SRBM
180
190
In Service
(M-7/8610)
SRBM = Short-range ballistic missile, 70-1000 km (43-620 mi.)
MRBM = Medium-range ballistic missile, 1001-3000 km (621-1860 mi.)
7 CRS analysts compiled the table based on unclassified reports of the government, public
media, and institutional data bases.

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North Korea, China, and Russia currently have other missiles in their
inventories or in development that are capable of reaching Japan, South Korea, or
Taiwan. Also because it will be several years before the United States, Japan, South
Korea, and Taiwan can deploy effective missile defenses, it is important to predict
the missile capabilities of potentially hostile countries several years from now. The
characteristics of other deployed missiles and missiles in development that were not
addressed in the DoD report are described in Table 2. Intercontinental ballistic
missiles (ICBMs) and submarine launched ballistic missiles are included in this
listing even though TMD systems have little or no capability to defend against them.
(This point is discussed later.) Surface-to-surface missiles deployed or being
developed by South Korea and Taiwan are listed because of their possible use as
deterrent or counterforce. U.S., British, and French missiles are excluded from the
chart.
Table 2. Other Missiles in the Region
Type
Range (km)
Payload (kg)
Status
NORTH KOREA
Taep’o-
IRBM
4,000-
?
In Development
dong-2
6,000
Two stage
CHINA
CSS-2 (DF-
MRBM
2650/
2,150
In Service
3/3A)
2800
CSS-3 (DF-
ICBM
5,500
2,200
In Service
4)
CSS-4 (DF-
ICBM
12,000/
3,200
In Service
5/5A)
13,000
CSS-5 (DF-
MRBM
2,500
600
In Service
21)
Nuclear
CSS-N-3
SLBM
1,700
600
In Development
(JL-1)
DF-31/JL-2
ICBM/
8,000
700
In Development;
SLBM
Tested 8/2/99
DF-41
ICBM
12,000
800
In Development
RUSSIA
SS-1 Scud
SRBM
300+
1,000
In Service
SS-19
ICBM
10,000
43,500
3 Deactivated
Stiletto
SS-21
SRBM
120
482
In Service
Scarab
SS-24
ICBM
10,000
40,500
Modernized w/
Scalpel
one warhead

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Type
Range (km)
Payload (kg)
Status
SS-25
ICBM
10,500
1,000
In Service, One
Sickle
Warhead
SS-27 Topol
ICBM
10,500
?
In Production
M
SS-N-20
SLBM
8,300
2,270
In Service
Sturgeon
SS-N-23
SLBM
8,300
1,360
In Service
Skiff
SOUTH KOREA
NHK-1
SRBM
180/250?
300
In Service
NHK-A
SRBM
300-665
300
In Development
(Hyon Mu)
ATACMS
SRBM
160
1670
Ordered
TAIWAN
Ching Feng
SRBM
130
400
In Service
(Green Bee)
Tien Chi
SRBM
300
500
SSM version of
(Sky
Sky Bow II SAM.
Halberd)
Tested 2/97
Tien Ma
SRBM
600-950
500
In Development
(Sky Horse)
MRBM = Medium-range ballistic missile, 1001-3000 km (621-1860 mi.)
IRBM = Intermediate-range ballistic missile, 3001-5500 km (1861-3410 mi.)
ICBM = Intercontinental ballistic missile, 5501+ km (3411 + mi.)
SLBM = Submarine launched ballistic missile
Capabilities and Limitations of U.S. TMD Systems
The DoD report describes some of the characteristics of the various TMD
systems and their ability to cover the terrain with some degree of protection. It is
constrained by its unclassified status, limited time, and international political
sensitivities, and therefore does not describe the detailed capabilities of the missile
defense systems it considers for use by Japan, South Korea, and Taiwan. A reader
cannot determine how well the illustrative TMD systems would defend the potential
recipients, because the DoD report does not indicate:
! what specific missiles each TMD system is expected to be capable
of defeating, nor generally what types of missiles with what speeds,
ranges, trajectories, warheads, and penetration aids;
! where the TMD units would be located, especially the ship
positions;

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! what precise geographic area each TMD system is capable of
defending;
! how many incoming missiles each system could track and defeat at
one time;
! how quickly the system can be reloaded;
! how secure each system is from enemy attack and countermeasures;
or
! what percent of incoming missiles is likely to be defeated by the
TMD systems described or, asked another way, what the probability
is that all incoming missiles would be defeated.
The report and other DoD sources indicate NTW can intercept only those
missiles flying at more than 100 km altitude and that THAAD can intercept only
those missiles flying at altitudes of at least 40 km. Using a maximum range
trajectory, ballistic missiles with a range of 300 km or less will have a maximum
altitude well below 100 km; using a depressed trajectory (described at pages 11 and
12) short and medium range missiles may be able to reach some targets without
exceeding a maximum altitude of 40 km. Therefore it may be possible for some
theater ballistic missiles to fly under the coverage of the upper tier systems if they do
not have to fly long distances in the relatively heavy atmosphere. However, if North
Korea or China were to depress the trajectory of SRBMs or MRBMs, they would
have to redesign the guidance and control systems, the structural components, and
the reentry vehicle.8 As discussed elsewhere, TMD systems also have a very limited
capability against fast, long-range missiles (such as ICBMs).
There are differing views on the issues of saturation and exhaustion of TMD
systems. Many analysts have raised concerns about the large inventories of missiles
and missile launchers being accumulated by North Korea and China, as well as
several Middle Eastern countries. They argue that a simultaneous attack by scores
of missiles on a relatively small target area could overwhelm (saturate) allied missile
defenses and that over time, the supply of defensive missiles could be exhausted in
attempting to intercept all the incoming missiles. Some calculations by DoD refute
this contention: a multiple-layer missile defense, using a series of upper tier TMDs
(in a shoot, look, shoot engagement) and a salvo of lower tier TMDs, would
minimize the enemy’s ability to destroy a target, even if it launched a large number
of missiles simultaneously. Therefore, an attacking force would require a very large
number of missiles and launchers to mount an effective missile attack and may well
be deterred from doing so by the presence of an effective missile defense system.
Enemy decoys and countermeasures could increase the number of interceptors
required for an adequate defense. Offensive and defensive missile systems will
continue to evolve and the balance between them will be difficult to judge, at least
until the specific systems have been produced and tested in a realistic combat
environment.
8 According to DoD officials, the guidance system would have to be altered to set the missile
on a depressed course and the missile body and reentry vehicle would have to be altered to
withstand greater forces and heat generated while traveling in the atmosphere.

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Three TMD Systems Versus a Regional Missile Defense
System
The legislation called for a study of “a theater ballistic missile defense system
in the Asia-Pacific region that would have the capability to protect key regional allies
of the United States.” The requirement could have been interpreted to call for a study
of a single integrated regional TMD system. DoD officials have stated they did not
“suggest or imply a region-wide architecture network.”9 For several reasons the DoD
report considered separate systems for Japan, Korea, and Taiwan. According to the
report, the study was “based on the unique political and military threat environment
confronting each one.” (p. 4) Also, if DoD had discussed an integrated regional
program, it would have risked damaging U.S., Japanese, Korean, and Taiwanese
relations with China, while at the same time raising extensive technical and political
issues involved in making the various command, control, and communication
systems interoperable.
Japan, Korea, and Taiwan apparently have no plans to cooperate with each other
in developing or acquiring missile defense systems; indeed they have little
cooperation in any area of national security. In August 1999, Japan and Korea
conducted their first combined naval exercise. But the lack of current cooperation
would not necessarily preclude the United States from transferring some TMD assets
to each recipient, then integrating them with U.S. early warning satellites and radars,
communications, battle management, and firing units to establish a missile defense
system that could span the region.10 However, it would be political necessary for
Japan, South Korea, and Taiwan to agree to this integration. The United States
already shares early warning data with Japan, but it is unclear that Japan could
currently apply it to a TMD system.
In summary, the development of a regional system would raise a number of
political and economic issues, as well as military and technical issues, but might
produce more effective and efficient missile defense than would the three separate
systems. Additional resources might be required to form a regional TMD network,
or savings might be achieved by sharing certain systems and capabilities when
integrating three separate systems into a regional system. Many of these issues are
beyond the scope of the study requirement and the DoD Report but are raised in the
three sections of this report on Japan, South Korea, and Taiwan, and in the section
on U.S. Considerations in Cooperative Missile Defense. In its future deliberations,
it will be important for Congress to know if there are fundamental problems that
render a regional missile defense infeasible, impractical, or unaffordable, as well as
if there are significant benefits of regional cooperation.
9 Ballistic Missile Defense Organization, “Theater Missile Defense (TMD) and East Asia
TMD Briefing for Congressional Research Service,” March 18, 1999.
10 Some transfers might be prohibited by the Missile Technology Control Regime (MTCR)
or the Anti-Ballistic Missile (ABM) Treaty or constrained by other factors.

CRS-10
U.S. Missile Defense Systems That Were Not Evaluated
While section 1533(a) of the reporting requirement calls for “a study of the
architecture requirements for the establishment and operation of a theater ballistic
missile defense system in the Asia-Pacific region that would have the capability to
protect key regional allies of the United States,” section 1533(b)(1)(C) states the
report shall include: “a description of any United States missile defense system
currently deployed or under development that could be transferred to key allies of the
United States in the Asia-Pacific region to provide for their self-defense against
limited ballistic missile attacks.” Based on its reading of the legislative
requirement, DoD studied only U.S. theater missile defense systems and, therefore,
limited its discussion to systems similar to five primary U.S. TMD weapon
programs: PAC-3, NAD, THAAD, NTW Phase I and NTW Phase II. Because
section 1533(b)(1)(C) refers to any U.S. missile defense system, some may suggest
that additional U.S. missile defense systems and programs should be considered, such
as Airborne Laser (ABL). However, according to DoD, the ABL or Space-based
Laser (SBL) systems are not being considered for transfer out of the United States,
and for that reason and because of time constraints were not included in the study.
Because the legislation calls for a study of any U.S. missile defense system to
provide key allies with a defense against limited ballistic missile attacks, it may
have been appropriate to consider systems that would protect Japan, Republic of
Korea, and Taiwan against all classes of missiles rather than just some classes of
missiles. Because the territories are relatively small and relatively close to the likely
attacking countries, some may have assumed that theater missile defense systems are
effectively national missile defense systems and would protect these countries
against all or most ballistic missile attacks. Japanese, Chinese, and Russian officials
have indicated confusion over the terms or over the capabilities of TMD systems.11
Actually, Japan, South Korea, and Taiwan could be attacked by intercontinental
ballistic missiles (ICBMs), as well as by intermediate-range, medium-range, and
short-range ballistic missiles. TMD systems generally are not considered effective
against ICBMs because of the speed of the attacking missiles. The United States
plans not to test its TMD systems against targets traveling faster than 5 km/sec or
with ranges greater than 3,500 km, so will not be confident of their effectiveness
against ICBMs.12 (See page 14 for further discussion.) When the U.S. national
missile defense (NMD) system is developed, it may have the technology that, if
transferred or extended, could protect Japan, South Korea, and Taiwan against all
limited missile attacks. Not only does the DoD report exclude discussion of certain
missile defense systems (ABL and NMD), it also does not discuss the vulnerability
11 Ministry of Foreign Affairs spokesman Numata said, “the Americans call it theater missile
defense (TMD). We call it ballistic missile defense (BMD). There is a difference there in
the sense that the United States tends to think of it in theater-wide terms, whereas we think
of it purely in the context of the defense of Japan for the purpose of self-defense.” March
2, 1999. Chinese and Russian officials have complained that TMD systems in Asia may
degrade their strategic deterrence or violate the ABM Treaty.
12 Many analysts contend that NTW with additional sensors for early warning and long-
range tracking would be able to intercept ICBMs.

CRS-11
of Japan, South Korea, and Taiwan to attack by high-speed missiles such as ICBMs,
after the hypothetical acquisition of the TMD systems discussed.
How Are the Examples Different From U.S. TMD Systems?
The report indicates the illustrative TMD systems are similar to U.S. systems
under development, but it does not say how they might differ from U.S. systems.
DoD officials explained that they used the illustrative systems in the unclassified
report because the precise characteristics and capabilities of the TMD systems are
classified and because of the little time that was available to coordinate the report
throughout DoD. They also stated the characteristics of the illustrative systems were
relatively close to those of the systems being developed by the United States and that
differences did not have a profound effect on the results of the study.
How Would U.S.-Deployed TMD Contribute to Asian Defense?
Any TMD systems the United States deploys now or in the future with its
ground, sea, and air forces in Asia and the Pacific are likely to contribute to missile
defense of the region. U.S. TMD systems deployed in or near Japan, South Korea,
and Taiwan could provide them some missile defense, and the TMD systems they
acquire could contribute to the defense of U.S. forces. Whether one is studying a
region-wide system or three separate systems, the effects of relevant U.S. missile
defense systems fit the context of discussion.
What Territory Would Be Considered Protected?
The DoD report describes the TMD systems required to protect Japan, South
Korea, and Taiwan but does not clarify what territory would be protected. The report
and DoD briefing materials imply that the study refers to TMD systems that would
protect the four largest islands of Japan, but not necessarily the entire Ryukyu
Archipelago, Sakishima-gunto (the archipelago that stretches almost to Taiwan),
Senkaku Islands, Iwo Jima (Io To), or the Ogasawara (Bonin) Islands. The systems
discussed for the defense of Taiwan apparently do not protect the islands off the
Chinese mainland – particularly Quemoy and Matsu that are within artillery range of
the mainland. The systems described for South Korea may or may not protect the
islands Cheju Do or Ullung Do, and, according to the report, would not protect Seoul
from all North Korean missiles. If all the territories of the three countries are
included, the coverage of South Korea’s and Taiwan’s TMD systems would probably
overlap with Japan’s and might benefit from coordination through a regional TMD
system.
How Would TMD Affect the Regional Military Balance?
Although TMD systems are inherently defensive, they can also affect a regional
military balance by reducing the effectiveness of other countries’ deterrent and
offensive combat capabilities. The TMD systems may also provide missile
technology and command, control, communication, and battle management
technology that the recipients could apply to their offensive capabilities. An
imbalance could lead to an arms race including missiles, missile defenses, WMD,

CRS-12
and advanced conventional weapons. China and North Korea are particularly
concerned that regional TMD and U.S. NMD will threaten their security systems.
Russia is also concerned about the effect of a U.S. NMD on its strategic forces.
Therefore, some U.S. analysts think missile defense can be destabilizing. Some
analysts suggest that by encouraging Japan and South Korea to acquire missile
defense systems to counter North Korean missiles, the United States is undercutting
its own efforts to persuade Pyongyang to relinquish its long range missiles. Regional
TMD efforts, according to these analysts, send signals of containment and military
supremacy, while U.S. diplomatic efforts are trying to draw North Korea into normal
relations. Others insist TMD will deter or defeat missile attacks and are therefore
stabilizing. Other countries, in their view, should not be offended by our defenses.
Such factors were not within the scope of the DoD report but may be of interest to
Congress as it considers the advisability of supporting regional TMD programs.
How Do TMD Options Suggested Compare to Other Options?
The five missile defense options discussed in the mandated DoD report address
only one aspect of missile defense: active defense. DoD has defined TMD as
comprised of four operational pillars: active defense, passive defense, attack
operations, and command, control, communications, computers, and intelligence
(C4I) (essential for any of the other pillars).13 Although it is beyond the scope of the
legislative requirement for the DoD report, the limitations of not having all aspects
of missile defense discussed in a single report are worth noting. Similarly, the
missile defense options were not presented in the broader context of policies to
counter WMD and missiles. These broader policies might include detecting and
monitoring, preventing proliferation, deterring deployment and use, defending
against WMD, and reducing world WMD inventories.
Assessment of DoD Report for Japan
The Missile Threats to Japan
North Korea, China, and Russia have the capability to attack Japan with ballistic
missiles. Tokyo’s immediate interest in TMD is based on the threat from North
Korea.14 North Korea’s Nodong 1 MRBM with a range of 1,000-1,300 km (620-800
mi.) could reach most of Japan and the two-stage Taep’o-dong 1 MRBM with a range
of 1,500-2,000 km (900-1,200 mi.) could reach all of Japan. On August 31, 1998,
North Korea fired a three-stage rocket (apparently a Taep’o-dong 1 with a solid-fuel
third stage) over Japan ostensibly in a failed attempt to launch a satellite. If it is
ultimately successful, the three-stage rocket might have a range of more than 5,000
13 DoD, “Doctrine for Joint Theater Missile Defense,” Joint Pub 3-01.5, February 22, 1996.
14 In response to North Korea’s August 31, 1998 ballistic missile shot over Japan, Sadaaki
Numata, spokesman for Japan’s Foreign Ministry said: “We are seriously concerned about
this because the deployment of missiles by North Korea does affect Japanese security and
it also affects peace and stability in Northeast Asia.” New York Times, September 1, 1998.

CRS-13
km (3,100 mi.).15 North Korea is also reportedly developing a two-stage Taep’o-
dong 2 with a range of 4,000-6,000 km (2,500-3,700 mi.) and might extend its range
by adding a third stage. North Korea reportedly is developing, or has developed,
nuclear, chemical, and biological weapons that it may be able to deliver with its
ballistic missiles.
The extensive ballistic missile inventory of the People’s Republic of China, too,
is a potential threat to Japan. Officially, the Japanese leadership has not made any
public statements suggesting any connection between China’s ballistic missiles and
Tokyo’s current interests in TMD.16 However, a security specialist with the Institute
of International Policy Studies in Tokyo believes that “North Korea provides a good
excuse [for TMD], but as a matter of fact the primary target is China.”17 China has
two medium-range ballistic missiles that can hit Japan: the CSS-2 with a range of
2,800 km and the CSS-5 with a range of 1,800 km (conventional warhead) or 2,500
(nuclear). China’s CSS-3 (5,500 km) and CSS-4 (12,000/13,000 km) ICBMs could
also reach Japan, and the PRC continues to improve its missile force with the
development of at least one new mobile ICBM (DF-31), submarine launched
missiles, and new cruise missiles. China has nuclear and chemical weapons and
probably has biological weapons. It is known to have nuclear warheads for its
strategic missiles.
China could attack Japan with ICBMs which may fly too fast for the proposed
TMD systems to intercept reliably. Also, it is possible that North Korea could
modify the trajectory of its missiles to increase their effectiveness against a missile
defense system in Japan. Conceivably, North Korea could launch a three-stage
Taep’o-dong 1 or a Taep’o-dong 2 on a very steep (lofted) trajectory to a high
altitude, so that it would enter Japanese airspace at such a high speed (over 5 km/sec)
that planned TMD systems could not reliably intercept it.18 On a lower (depressed)
trajectory, Taep’o-dong missiles could theoretically attack Japan at a very high
velocity while spending less time above 100 kilometers of altitude where they might
be vulnerable to NTW. A depressed trajectory could deliver a missile from North
15 CBS Evening News, CBS Worldwide Inc., [http://www.wusatv9.com], Sept. 15, 1998;
New York Times, September 15, 1999.
16 For example, in the annual Defense of Japan white paper 1998, by the Japanese Defense
Agency, under the section detailing number and types of ballistic missiles that China has,
no mention is given assessing the implications to Japanese security of the existing Chinese
ballistic missile systems, though it is pointed out that the missile force is growing and
qualitative improvements are being made.
17 “The Concept: An Asian Missile Shield,” Christian Science Monitor, April 8, 1999, p. 12.
18 Spring, Baker. “Successful Missile Defense Test Shows Technology Works,” The
Heritage Foundation Executive Memorandum, no. 608, June 18. Mr. Baker contends that
neither THAAD nor NTW is capable of downing a Taepo’-dong 1 missile because of its
speed. He estimated it had a maximum speed of 7-8 km/sec in the August 1998 launching.
U.S. TMD systems have not been and are not planned to be tested against targets that travel
over 5 km/sec. The Taepo’-dong 2 will probably have a greater maximum speed. But with
sufficient early warning and cueing sensors, NTW might be able to intercept ICBMs with
speeds over 5 km/sec, as many analysts have suggested NTW be used for national missile
defense.

CRS-14
Korea to Japan very quickly, reducing the time available to locate and identify the
attacking missile, obtain authorization to fire the interceptor, and to destroy the
attacking missile.19 However, it is questionable whether North Korea or China will
have built missiles, reentry vehicles, or warheads able to withstand the heat and stress
of traveling through the atmosphere for the longer periods required by a depressed
trajectory. The additional weight of material to strengthen the missile components
and protect them from heat could require a smaller warhead or greater thrust. But
that additional weight should not be a problem for Taep’o-dong missiles that have
enough thrust to send them far beyond Japan. A depressed trajectory also reduces
accuracy.20
The stress and heat generated in a depressed trajectory, and the possibility of the
reentry vehicle colliding with rocket stages and shrouds jettisoned in the atmosphere,
might be reduced by a “shaped trajectory,” i.e., one that differs substantially from a
ballistic trajectory. In this trajectory, a missile ascends on a steep path, then turns
“when outside the atmosphere to fly more nearly parallel to the earth’s surface,”
discards used stages in space, and reenters the atmosphere at a selected angle of
descent.21 North Korea or China might in the future be able to defeat proposed
theater missile defense systems by modifying the speed, flight time, and altitude of
missile attacks. Although these modifications are theoretically possible, and some
scientists contend the United States and Russia could accomplish them, there is no
publicly available information to indicate China or North Korea will attempt to or
will be able to modify their missiles in these ways.
Russia maintains a sizeable missile force consisting of ICBMs, SLBMs, and
cruise missiles that could strike Japan. The missile defense system Japan is
contemplating and the systems discussed in the DoD report do not appear to respond
to the threat of Russian missiles nor would they be well suited to defend against such
a threat.
The DoD report does not specify what penetration aids and countermeasures are
likely to be associated with North Korean, Chinese, or Russian missiles that may
threaten Japan. The effectiveness of missile defenses may be degraded by decoys
(including balloons), chaff, submunitions, spin-stabilized reentry vehicles (RVs), RV
reorientation, radar absorbing material (stealth), modified trajectories, distracting
heat sources, or electronic countermeasures including jammers. The use of multiple
launchings or multiple warheads could have a similar effect by requiring the defense
to acquire, track, and engage more weapons at one time.22 The unclassified version
19 CRS Report 90-329 F, Fast-Trajectory Strategic Ballistic Missiles: Characteristics,
Military Uses, and Implications, by Jonathan Medalia, July 10, 1990.
20 Gronlund, Lisbeth and David C. Wright. “Depressed Trajectory SLBMs: A Technical
Evaluation and Arms Control Possibilities,” Science & Global Security, v. 3, 1992, pp. 101-
160.
21 Ibid., pp. 9-10.
22 The DoD report states, “there was insufficient time to examine the effects of suppression
of TBMD systems by a potential aggressor, robustness against maximum aggressor raid
(continued...)

CRS-15
of the 1999 national intelligence estimate on the ballistic missile threat reported that,
“Russia and China each have developed numerous countermeasures and probably are
willing to sell the requisite technologies.” It also judged that countries such as North
Korea, Iran, and Iraq that are developing long-range missiles, could develop such
countermeasures “by the time they flight test their missiles.”23
Potential Capabilities and Limitations of TMD Systems
The DoD report concluded the best missile defense option of those considered
to defend Japan against North Korean Nodong or Taep’o-dong 1 missiles would be
a shipboard NTW Block II-like system. “One ship position is sufficient to provide
full national coverage.” (p. 8) This system would be able to fire twice (shoot-look-
shoot) at North Korean missiles directed at the central portion of Japan. On the
other hand, four ship positions would be required for an NTW Block I-like system
to “provide nearly complete coverage of Japan with substantial shoot-look-shoot
opportunities over much of Japanese territory.” (p. 8)
The report also analyzed two land-based systems based on PAC-3 and THAAD.
It found that more than 100 PAC-3-like systems (augmented by a THAAD-like radar)
would be required for a country-wide defense of Japan with this system. The report
explained the purpose of examining the PAC-3 system “was simply to demonstrate
the large number of fire units that would be required to accomplish a ballistic missile
defense for Japan.” (p. 8) Six THAAD-like systems, or four THAAD-like systems
with three additional THAAD-like radars would be required to cover all, or nearly
all, of Japan.
The report did not indicate how many Navy Area Defense-like ships would be
required to provide lower-tier protection of Japan, although it did evaluate this
system for lower-tier protection of South Korea and Taiwan. Probably because of
NAD’s limited ability to provide protection for inland facilities and population
centers, it was not discussed for Japan’s defense against Nodong and Taep’o-dong
missiles.
The report does not comment on the ability of any of these missile defense
systems to defend against a North Korean Taep’o-dong 1 with a third stage, Taep’o-
dong 2, Chinese MRBMs with ranges greater than 2,000 km, or Chinese or Russian
ICBMs. In keeping with the ABM Treaty demarcation agreement, the United States
will not test its TMD systems against targets with the speed of a strategic missile
(over 5 km/sec.), so it would not be safe to assume the TMD systems would be
effective against these missiles. There was also no indication in the report that Japan
would enhance the capability of the U.S. systems or test them against faster missiles.
(However, on page 5, the DoD report said a source of early warning, such as
overhead surveillance and long-range phased-array early-warning radar is essential
22 (...continued)
sizes, or countermeasures which could be employed on theater ballistic missiles (TBMs).”
(P. 4)
23 U.S. National Intelligence Council. “Foreign Missile Developments and the Ballistic
Missile Threat to the United States Through 2015.” September 1999, p. 14.

CRS-16
for effective TMD.) It would thus appear that the missile defenses analyzed in the
DoD report were not considered as a reliable defense against these faster, longer-
range missiles. But, if passed, the Realistic Tests for Realistic Threats National
Security Act of 1999,24 would require DoD to test NTW and THAAD “against target
missiles with velocities not less than the maximum velocity of the Taepo Dong I
missile of North Korea.” The bill also calls on DoD to review changes to the
configuration of NTW and THAAD to increase the interceptor speed beyond three
kilometers per second and to allow the interceptors to use a wide variety of sensors.
TMD systems, or at least upper tier TMD systems, would presumably be able
to protect against Chinese MRBMs — CSS-5 (1,800 or 2,500 km) and CSS-2 (2,800
km) – fired on a standard trajectory without extensive or sophisticated penetration
aides. But, more TMD ship positions or land-based firing units and radars than
envisioned in the DoD architecture options would be required to defend against these
Chinese missiles and against future Chinese SLBMs because they could be fired at
relatively high speeds from a wide range of locations in China, whereas missiles
launched in North Korea, “would come from a concise attack area.” (p. 7)
The report does not comment on the capability of the various TMD systems to
overcome modified trajectories and penetration aids (discussed on page 12 above).25
Depending on the expected capabilities of the North Korean, Chinese, and Russian
missiles, any missile defense system that is to be able to defend Japan must be able
to overcome some or all of these countermeasures.
Japanese Considerations26
The Japanese have long been intent on maintaining a close security relationship
with the United States, based on the Treaty of Mutual Cooperation and Security
signed in 1960. More recently, Japan has become interested in supplementing its
own self-defense forces with missile defense systems, primarily to counter the North
Korean missile threat. In August 1999, the United States and Japan signed an
agreement to conduct joint research on four components of the NTW system: nose
cone, 2nd stage propulsion, sensor, and kinetic warhead.27 Japan had committed
approximately $8 million to fund their first year of this joint effort and the Japan
Defense Agency submitted a preliminary budget request of almost $20 million for
the second year.28 According to DoD officials, the Japanese technological
contribution could be significant.
24 H.R. 2596, introduced by Mr. Vitter on July 22, 1999.
25 DoD noted this omission was due to insufficient time.
26 The DoD report stated, “Because the focus of this study is possible TMD architecture, it
does not address their feasibility or desirability from political, economic, or other security
perspectives. A detailed discussion of these important facets of the issue is outside the
mandate and scope of this paper.”
27 BMDO and “Japan Missile Defense Tops R&D Funding List,” Defense News, March 22,
1999, p. 14.
28 Usui, Naoki. “Japan Aims to Boost Ballistic Missile Research Funds,” Defense News,
September 20, 1999, p. 24.

CRS-17
The Japanese are well aware that China objects to the missile defense
cooperative program because it signals stronger U.S.-Japan military ties, may portend
increased Japanese militarization, might degrade China’s capability to project power
through missile attacks, and China is particularly concerned that the Japanese missile
defense system might cover Taiwan. While Japan does not wish to antagonize
China, it has apparently concluded it needs a system that is effective against North
Korean missiles, which would also be effective against some of China’s missiles.
Japanese leaders have also been constrained by Article Nine of the country’s
Constitution that renounces war and the threat or use of force as a means of settling
international disputes. Japan has traditionally eschewed offensive weapons and
foreign deployments. It has also avoided security relationships (including missile
defense) with its Asian neighbors and might be reluctant to deploy its missile
defenses in a way that would contribute to another country’s defense or that would
intrude into the territorial waters or airspace of another country. Also, Japan is
apparently not currently considering defense systems like the Airborne Laser (ABL)
or an equivalent to the U.S. National Missile Defense (NMD), partly because they
could be construed as offensive or strategic systems. (However, as mentioned above,
the Japanese do not consider the proposed systems to be theater missile defense, but
missile defense of the country.) But Japan may be able to adopt somewhat more
aggressive missile defense measures (such as ABL, Space-Based Laser, or boost-
phase intercept) if it approves legislation currently under consideration that would
allow pre-emptive strikes against another nation when the threat of attack is
imminent.29
Japanese missile defense cooperation with its Asian neighbors might also be
restricted by the Three Principles of Arms Exports and related guidelines which
prohibit arms exports to communist countries, countries under a UN embargo, or
countries involved in, or likely to be involved in, armed conflict. Arms transfers to
other countries are restrained “in conformity with the spirit of the Constitution and
the Foreign Exchange and Foreign Trade Law.”30
Japan’s preference for NTW over THAAD, which may employ space-based
sensors, is reportedly partially based on the country’s policy against the military use
of space. The DoD report acknowledges that some form of early warning and long
distance tracking, which could be space-based, would be required for an effective
TMD. It would probably need equipment and data in addition to the early warning
the United States has been sharing with Japan since 1996. Japan is developing an
indigenous Information Gathering Satellite System and is acquiring some U.S.
technology for the system.
29 Financial Times, “LDP debates military strikes strategy,” February 22, 1999, pg. 1. In
March 1999, the Japanese Prime Minister’s deputy press secretary said, “it is legally
possible for Japan to exercise the right of self-defense and attack bases of an enemy even
when Japan has not yet suffered any realistic damage.” Reuters, March 9, 1999.
30 Anthony, Ian (ed.). Arms Export Regulations. SIPRI., Oxford University Press, 1991, p.
106. Guidelines were first established in 1960, expanded in 1962, proclaimed as the Three
Principles in 1967, elaborated in 1976, and interpreted as they apply to the United States in
1983.

CRS-18
Cost is another important factor to the Japanese government. Acquisition and
operation of a comprehensive and effective missile defense system would be a large
and controversial expense for Japan’s Defense Agency and Self-Defense Forces.
Additionally, Japanese industry has become leery of joint development projects and
sharing its commercially-useful technology, even though the Japanese government
wants the benefits of advanced U.S. military technology, and Japanese industry wants
the financial and technological gains that can be associated with defense contracts.
THAAD would also occupy much more land – a scarce resource in Japan – and
would offer less opportunity for Japanese participation in system development than
would NTW.
Assessment of DoD Report for Republic of Korea
Missile Threat to the Republic of Korea
The DoD report used only the North Korean short range ballistic missile
capability to represent the threat to the Republic of Korea, while excluding the
potential threat from Chinese and Russian missiles.31 North Korea has hundreds of
domestically-produced Scud-B variants (100 and 300 km range) and Scud-C (500
km) missiles that could deliver high explosive or chemical warheads or, possibly,
biological warheads.32 Pyongyang is believed to have sufficient fissile material for
one or two atomic weapons and may possibly have produced such weapons.33 North
Korea also manufactures the Nodong MRBM and has tested the Taep’o-dong 1
MRBM, neither of which was considered. The DoD report said that because of the
relatively small size of South Korea (380 km north-to-south and 260 km east-to-
west), “the ranges of the ballistic missiles that can be used are restricted.”
Potential Capabilities and Limitations of TMD Systems
Five TMD options were examined by DoD and discussed in its report. The best
option included four THAAD-like systems and seven PAC-3-like systems. This
combination would provide coverage of “all of the country beyond the immediate
reach of very short-range ballistic missiles.”34
The critical feature for the coverage achieved by this architecture is the minimum
intercept altitude for the endo-exo upper tier [THAAD] system. Able to intercept
TBMs flying to an apogee as low as 40 kilometers, the endo-exo upper tier
system could reach most of the threatening trajectories. The lower tier [PAC-3]
system would be used to protect Seoul and its environs. ...
31 The report describes “the architecture requirements for the defense of the ROK against
North Korean missiles....” (P. 10)
32 U.S. Department of Defense. Proliferation: Threat and Response, November 1997, p. 8.
33 Unless North Korea has received extensive assistance from another country that has
developed and tested nuclear weapons, it is doubtful it has a reliable nuclear warhead for
its missiles.
34 DoD Report, p. 11, and TMD briefing by BMDO.

CRS-19
In the case of the THAAD-like... system, the high endo minimum intercept
altitude would preclude engagements for threats attacking the northern portions
of the ROK.35
This appears to indicate that THAAD-like systems could intercept North Korean
SCUD-Bs and Cs that climb above 40 km, and that PAC-3-like systems deployed
around Seoul might intercept some SCUDs that do not reach 40 km altitude.
Apparently not covered by the THAAD/PAC-3 combination are very short-range
North Korean missiles (perhaps FROGs and other battlefield rockets, as well as very
short-range SCUDs) deployed near the DMZ. The very short flight time is another
factor that makes it difficult to intercept missiles fired at Seoul from close range.
Even some North Korean artillery is within range of Seoul (just 40 kilometer/24
miles from the border with North Korea). As noted, SCUD, Nodong, and Taep’o-
dong missiles fired with a modified trajectory may exceed the capabilities of PAC-3
and THAAD.
Less effective options discussed in the report included:
! 25 PAC-3-like units to “cover the assets identified as critical,”
! 11 NA-like ships to provide protection to coastal areas,
! 1 NTW-Block I-like ship and 25 PAC-3-like units,
! 1 NTW-Block II-like ship and 19 PAC-3-like units.
The report notes that a larger deployment of PAC-3s would allow coverage of
more of South Korea than just the identified critical assets. The Navy Area Defense-
like systems “could not reach far enough inland to defend all critical assets and
population centers against all threat trajectories,” and the NTW-like system “could
not defend the northern two-thirds of the ROK against low-flying short-range
TBMs...most North Korean threats....”36
The report does not comment on the capability of the various TMD options to
overcome modified trajectories and penetration aids, such as decoys, chaff,
submunitions, multiple-simultaneous launchings, and electronic countermeasures.37
Depending on the expected capabilities of the North Korean, Chinese, and Russian
missiles, any missile defense system that is to be able to defend South Korea may
have to overcome some or all of these countermeasures.
Republic of Korea Considerations
South Korea officials are quite concerned by the North Korea missile threat, and
maintain a close military alliance with the United States while they work cautiously
toward reunification of the Korean Peninsula. Since 1979, the U.S. Army has
maintained one Patriot surface-to-air missile battalion at air bases south of Seoul to
protect key U.S. and South Korean fighter aircraft capabilities. Korean officials
considered, but were not initially anxious to purchase or participate in U. S. missile
35 Ibid, pp. 11, 12.
36 Ibid.
37 DoD noted this omission was due to insufficient time.

CRS-20
defense systems. But in early November 1999, DoD announced that South Korea
had initiated competition for a missile defense system, the SAM-X program. The
system is planned to be able to intercept aircraft at a distance of 60 km and missiles
at a distance of 20 km. It will be able to track four targets at once. Raytheon will
probably compete with a proposed system of 14 PAC-3 fire units (armed with PAC-2
Guidance Enhanced Missiles) at an estimated cost of $4.2 billion. A follow-on
system, the medium-range surface-to-air missile or M-SAM, is to have a 100 km
range.38
North Korea’s strident opposition to South Korean missile defense was
apparently not a significant factor in Seoul’s initial reluctance. Missile defenses were
not the top priority of the ROK military, partly because of their inability to guarantee
the safety of Seoul and adjacent military units. Also, the Asian financial crisis
reduced funds even for higher priority military programs. ROK officials considered
acquisition of the Russian S-300 theater missile defense system, which it might have
been able to obtain in exchange for relief of Russian debt to the country. The United
States strongly urged South Korea not to acquire the Russian system that would not
be compatible with U.S. military equipment. Seoul also considered the development
of its own missile force to deter a North Korean missile attack. ROK officials are
currently negotiating to release Seoul from its 1979 agreement with the United States
not to develop a missile with a range greater than 180 km. South Korea would prefer
to join the multilateral Missile Technology Control Regime and be allowed to
produce missiles with ranges of 300 km or more.
Assessment of DoD Report for Taiwan
Missile Threats to Taiwan
Scale of Attacks. The missile threat posed by the People’s Republic of China
(PRC) to Taiwan is wide-ranging, uncertain, and expanding. As the DoD report
pointed out, Taiwan faces an “evolving threat” from “multiple directions.” (p. 14)
Short-range ballistic missiles (SRBMs) and medium-range ballistic missiles
(MRBMs) could be launched from many areas in the large territory of the PRC.
Moreover, the DoD report noted that the PRC has a range of options, including:
limited firings of 1-3 missiles, medium-scale firings of several missiles at Taiwan’s
military targets, and large-scale firings against many targets. However, the DoD
analysis considered only attacks of a few (less than five) SRBMs or shorter range
MRBMs.39 At the same time though, the DoD report warned of a PRC missile
buildup, saying that the threats faced by Taiwan from PRC short- and medium-range
ballistic missiles “are expected to increase significantly over the next several years.”
38 Jane’s Defence Weekly, September 29,1999, p. 17; Inside Missile Defense, Nov. 17, 1999,
p. 3.
39 Interview with DoD.

CRS-21
Scope of Threat. Apparently due to the legislative requirement that the
Pentagon study architecture options for TMD systems to protect Japan, South Korea,
and Taiwan, the DoD report limited its discussion to theater ballistic missiles (less
than 3,500 km in range). However, the ballistic missiles available to the People’s
Liberation Army (PLA) cover a wider range, including ICBMs with much longer
range and higher speed.40 (See the table below.) The PRC has also worked on
developing submarine-launched ballistic missiles (SLBMs) that could also pose an
additional threat to Taiwan. The DoD report did not specify the PRC ballistic
missiles that could threaten Taiwan except to imply that shorter-range missiles in this
context have a range of less than 300 km (190 mi) and longer-range missiles have a
range of about 3,000 km (1,860 mi) (p. 14). However, the DoD analysis considered
some SRBMs and MRBMs (i.e., conventionally-armed CSS-5s) with ranges of 1,800
km or less.
Wide Range of Possible Threats. The PLA has at least three classes of
SRBMs that could be used against Taiwan. The PRC launched the 600 km (380 mi)-
range M-9 (PRC designation), or CSS-6 (U.S. designation), SRBMs into waters near
Taiwan in 1995 and 1996. There are reportedly up to 50 launchers for the M-9,
although the number of missiles can be much larger than the number of launchers,
because launchers can be used repeatedly.41 The M-11, or CSS-7, is an SRBM with
a range of about 300 km (190 mi), sufficient to fly over the Taiwan Strait (about 100
miles wide). Like other newer PRC missiles, it can be fired from a mobile
transporter-erector-launcher (TEL). However, there are questions about the status of
the M-11 missile and whether a new version with a range of over 300 km will be
available. The Secretary of Defense’s February 1999 report on Taiwan security
reported that the M-11 “has not yet entered the PLA’s inventory; and an improved,
longer range version may be under development.”42 The report also warned of a PRC
missile build-up, saying that “within the next several years, the size of China’s
SRBM force is expected to grow substantially.” Taiwan’s Defense Ministry said in
February 1999 that the PRC has more than 100 M-class missiles in storage that could
target Taiwan.43 According to news reports in early 1999, citing a classified
Pentagon report, China increased its SRBM deployment on the coast across from
Taiwan from 30-50 in 1995-1996 to 150-200 SRBMs (including M-9s, and possibly
M-11s). Moreover, the PLA plans to increase its number of SRBMs to 650 by
2005.44 The PLA also has M-7 (CSS-8) SRBMs that were derived from HQ-2
40 For details and sources, see CRS Report 97-391, China: Ballistic and Cruise Missiles, by
(name redacted) and (name redacted). See also, U.S. Air Force, National Air Intelligence
Center (NAIC), “Ballistic and Cruise Missile Threat,” April 1999.
41 NAIC.
42 Secretary of Defense, “The Security Situation in the Taiwan Strait,” Report to Congress
Pursuant to the FY99 Appropriations Bill, February 1, 1999.
43 “Citing Threat of Chinese Missiles, Taipei Calls Defense Inadequate,” Reuters, February
11, 1999.
44 Walker, Tony and Stephen Fidler, “China Builds Up Taiwan Missiles,” Financial Times,
February 10, 1999; Bill Gertz, “China Moves Missiles In Direction of Taiwan,” Washington
Times, February 11, 1999.

CRS-22
surface-to-air missiles. The CSS-8 has a short range of only about 180 km (90 mi),
sufficient to cross the strait and hit targets in western Taiwan in about two minutes.45
PRC
U.S.
Range (km)/
Launch
Type
Designatio
Designatio
Launchers*
Warhead (kg)
platform
n
n
SRBM
DF-15/
CSS-6
600/500
<50 mobile TEL
M-9
SRBM
DF-11/
CSS-7
300/500
? mobile TEL
M-11
SRBM
8610/
CSS-8
180/190
? mobile
M-7
launcher
MRBM
DF-3A
CSS-2
2,800/2,150
<50 land-mobile
MRBM
DF-21
CSS-5
1,800/ ?
<50 mobile
TEL
Conventional
MRBM
DF-21
CSS-5
2,500/600
? mobile TEL
Nuclear
ICBM
DF-4
CSS-3
5,500/2,200
<25 silos and land-
mobile
ICBM
DF-5A
CSS-4
13,000/3,200
<25 silos
*Each launcher may launch more than one missile.
There are also at least two classes of Chinese MRBMs that could be used
against Taiwan. The older DF-3A (CSS-2) MRBMs, with up to 50 launchers, have
a range of approximately 2,800 km (1,700 mi). The newer, solid-fuel DF-21 (CSS-5)
MRBMs, armed with conventional warheads, travel about 1,800 km (1,100 mi), with
up to 50 launchers deployed.46 Another version of the CSS-5, with a 2,500 km range,
is believed to be armed with a lighter nuclear warhead, but the DoD report did not
consider this nonconventional missile to be targeted at Taiwan. These longer-range,
faster MRBMs would have been a greater challenge for the Taiwan TMD system and
may have required a more robust architecture.
While the DoD report did not discuss the threats from Chinese ICBMs, there are
also at least two classes of Chinese ICBMs that potentially could threaten Taiwan,
although they are believed to be deployed for strategic nuclear deterrence. The DF-4
(CSS-3) ICBM has a limited range of about 5,500 km (3,400 mi), and the DF-5A
(CSS-4) has a range of about 13,000 km (8,000 mi). While these ranges are longer
than needed to reach Taiwan, they can be changed depending on the amount of fuel,
45 Stokes, Mark A., “China’s Strategic Modernization: Implications for U.S. National
Security,” Paper for the Project for the New American Century, April 23, 1999.
46 NAIC.

CRS-23
the weight of the warhead, and the trajectory, including potentially a very high flight
path (lofted trajectory).
In addition, the PRC has been developing more modern ICBMs, including the
DF-31 that was test-launched on August 2, 1999, and SLBMs, including the JL-1
with a range of about 1,700 km (1,000 mi). Twelve JL-1s are intended to be
deployed on the PLA’s one XIA class nuclear-powered ballistic missile submarine
(SSBN), but the missile apparently has not yet been successfully deployed.47 A
follow-on JL-2 SLBM is also reportedly under development for deployment on
planned 094 SSBNs.
The trajectories and speed of the PRC’s ballistic missiles would affect defenses
against them. The DoD report provided some details on these questions. It said that
the SRBMs and MRBMs threatening Taiwan have apogees “outside the atmosphere”
and that “the medium range missile also has a re-entry speed likely to preclude a high
probability of intercept by lower-tier systems.”48 However, according to another part
of the DoD report and DoD sources, if China deployed and fired ballistic missiles
with shorter ranges (less than 300 km), these missiles could “remain inside the
atmosphere for the entire trajectory” and fly beneath the coverage of exo-
atmospheric, upper-tier TMD systems (such as NTW).49 Depressed trajectories of
ballistic missiles could reduce the effectiveness of, or possibly defeat, certain TMD
systems considered.
Apparently assuming a conventional role for China’s theater ballistic missiles
that threaten Taiwan, the DoD report did not discuss the warheads that may be
delivered by PRC ballistic missiles, which could carry conventional warheads or
WMD. While they may carry various types of conventional warheads, the M-11 and
M-9 SRBMs as well as the MRBMs are nuclear-capable. Some in Taiwan fear that
the PRC has not ruled out the use of WMD, including nuclear weapons, against
Taiwan.50 While previously serving as Chief of General Staff, Taiwan’s Defense
Minister Tang Fei reported to the legislature on the Chinese threat, including
modernization of nuclear weapons and ballistic missiles.51 On July 15, 1999, the PRC
government issued a report to refute the findings of the House Select Committee on
China (Cox Committee), and the PRC’s statement included the first official
acknowledgment that it has the neutron bomb.52 Neutron bombs kill large numbers
47 NAIC.
48 The report may be referring to both CSS-2 and CSS-5 MRBMs as having re-entry speeds
that are too fast for lower-tier missile defense systems.
49 The endo-atmospheric flight of a 300 km-range SRBM was also indicated by a briefing
by the Ballistic Missile Defense Organization (BMDO) of the Department of Defense,
March 18, 1999.
50 Liao, Hung-hsiung, “Should Taiwan Develop Strategic Nuclear Weapons?” Ch’uan-ch’iu
Fang-wei Tsa-chi, March 15, 1999, in FBIS.
51 Lai, Victor, “Top Military Leader Reports on Taiwan Defense Situation,” Central News
Agency, September 30, 1998, in FBIS.
52 People’s Republic of China, Information Office of the State Council, “Facts Speak Louder
(continued...)

CRS-24
of people with radiation without destroying buildings and equipment. Some analysts
considered this announcement to be a threat meant to intimidate Taiwan, since the
timing of the report came soon after Taiwan President Lee Teng-hui angered Beijing
on July 9, 1999, by saying that cross-strait relations are “special state-to-state ties.”53
As noted above, a PRC MRBM with a nuclear warhead would have a longer range
and higher velocity than one with a heavy high explosive warhead. Although it
would present a greater challenge to a TMD system and a greater risk to Taiwan, the
nuclear-tipped MRBM was not considered in the DoD report.
In addition, as a signatory to the Chemical Weapons Convention, China has
acknowledged that it has chemical weapon facilities and stockpiles.54 On May 21,
1997, the Clinton Administration imposed sanctions confirming that Chinese entities
had contributed to chemical weapon proliferation in Iran.55 As for biological
weapons, the U.S. Arms Control and Disarmament Agency reported in 1998 that
“there are strong indications that China probably maintains its offensive program.”56
Also, the DoD report did not specify what types of conventional warheads,
penetration aids, and countermeasures are likely to be associated with Chinese
missiles that may threaten Taiwan. Indeed, in September 1999, the Intelligence
Community publicly confirmed that China has developed “numerous
countermeasures” and likely is willing to sell the technology to other countries.57 The
effectiveness of missile defenses may be degraded by decoys, chaff, submunitions,
multiple-simultaneous launchings, modified trajectories, or electronic
countermeasures. The use of multiple warheads could have a similar effect by
requiring the defense to acquire, track, and engage more weapons at one time.58
Potential Capabilities and Limitations of TMD Systems
Taiwan’s Considerations. Taiwan has a number of options should it decide
to seek missile defenses beyond the Modified Air Defense System (MADS), a Patriot
52 (...continued)
Than Words and Lies Will Collapse by Themselves — Further Refutation of the Cox
Report,” July 15, 1999.
53 Faison, Seth, “Is China Waving a Bomb at Taiwan?,” New York Times, July 16, 1999.
54 Lippman, Thomas, “Poison Gas Treaty Process Reveals Previously Unknown Production
Sites,” Washington Post, September 28, 1997.
55 See CRS Issue Brief 92056, Chinese Proliferation of Weapons of Mass Destruction:
Current Policy Issues, by (name redacted).
56 U.S. Arms Control and Disarmament Agency, “Adherence to and Compliance With Arms
Control Agreements,” 1997 Annual Report.
57 National Intelligence Council, “Foreign Missile Developments and the Ballistic Missile
Threat to the United States Through 2015,” September 1999.
58 The DoD report states, “there was insufficient time to examine the effects of suppression
of TBMD systems by a potential aggressor, robustness against maximum aggressor raid
sizes, or countermeasures which could be employed on theater ballistic missiles (TBMs).”
(p. 4)

CRS-25
system, acquired in 1997 to protect Taipei. Taiwan may consider several factors in
selecting a system to counter the PRC’s possible use of SRBMs as well as longer
range ballistic missiles. The possibility that the missiles could carry non-
conventional as well as conventional warheads may require greater emphasis on the
interception of missiles over the PRC or over the sea, farther from Taiwan. A
Chinese attack with lofted ICBMs, depressed MRBMs, or shorter range missiles may
be able to defeat the TBMDs discussed. It is not clear how effective a sea-based
upper tier system would be if Taiwan were attacked with SLBMs launched from a
submarine east, north, or south of the island.
DoD Report’s Options. The DoD report noted that either the land-based or
the sea-based lower tier system could adequately defend “most of Taiwan’s critical
assets,” but neither system could provide “any defense” against longer range theater
ballistic missiles. Thus, the report said that “to address the full range of threats
[SRBMs and MRBMs], three land- and sea-based upper tier options were explored.”
The DoD report found that one land-based upper tier system, with an additional
THAAD-like radar, could cover the “entire island of Taiwan” and could intercept
both missiles flying inside the atmosphere (endo-atmosphere) and outside (exo-
atmosphere). Alternatively, one sea-based upper-tier system, like NTW, with only
one ship position, could cover “all of Taiwan.” A sea-based option could be the NTW
SM-3 Block I Missile (with Aegis Spy-1 radar) or the NTW Block II system.59
However, while the DoD report found that either one land-based or one sea-
based upper-tier option is sufficient to defend Taiwan, it did not compare their
respective advantages or disadvantages. Both sea-based upper tier systems are exo-
atmospheric and would not intercept SRBMs or MRBMs on trajectories that remain
inside the atmosphere. While THAAD is expected to have the capability to defend
against ballistic missiles flying inside the atmosphere as low as 40 km, NTW has a
minimum intercept altitude of about 100 km (p. 11). On the other hand, the NTW
system could intercept some incoming missiles (possibly with non-conventional
warheads) in their ascent, mid-course, and descent phases outside the atmosphere,60
potentially farther away from Taiwan. The DoD report also did not discuss the
effectiveness and vulnerability of various possible locations of the one ship position
needed for a sea-based, upper-tier option (i.e., in the Taiwan Strait or east of Taiwan).
Alternative Options. Thus, Taiwan may need to further enhance defenses
against the PRC’s missiles with a combination of both an upper tier system and
another system to defend against low altitude missiles and to provide “layered
defenses” (or “defense-in-depth”). Rather than the DoD report’s options of a single
system similar to THAAD, NTW Block I, or NTW Block II, Taiwan’s defense may
well require a set of alternative options (with one or more units of each system):
59 The DoD report states the upper tier systems could protect all of Taiwan, although it also
says the upper tier systems could not defend the upper portions of South Korea. NTW could
not defend the upper 250 km of South Korea, although it can reportedly defend all of
Taiwan which is only 175 km from mainland China. (Pp. 10 and 14)
60 BMDO interview.

CRS-26
1. Land-based Lower Tier (PAC-3) and Sea-based Exo Upper Tier (NTW Block
I or Block II), or
2. Sea-based Lower Tier (NAD) and Sea-based Exo Upper Tier (NTW Block
I or Block II), or
3. Land-based Lower Tier (PAC-3) and Land-based Endo-Exo Upper Tier
(THAAD), or
4. Sea-based Lower Tier (NAD) and Land-based Endo-Exo Upper Tier
(THAAD).
Limits to Missile Defense. Nonetheless, in the context of military
considerations discussed within the scope of the DoD report, there are limitations to
Taiwan’s pursuit of the above missile defense options.
First, while the upper-tier missile defense systems provide better protection for
Taiwan against Chinese MRBMs or high altitude SRBMs, they are not expected to
reach initial operational capability until after 2007. On the other hand, the lower-tier
systems are expected to be operational sooner (PAC-3 in FY 2001 and NAD in FY
2003).
Second, with the PRC’s reported build-up of its missile force and its range of
options (from limited to large-scale missile firings), there may be concern that
Taiwan could face a large-scale missile threat from many directions that could strain
its missile defenses. Furthermore, a ballistic missile could cross the Taiwan Strait
in only minutes, making it very difficult for decision-makers to react and missile
defenses to intercept. For example, a ballistic missile with a range of 600 km, such
as the M-9, would travel at a maximum velocity of 2.4 km/second, crossing the Strait
in a few minutes. In spring 1999, Assistant Secretary of Defense Franklin Kramer
provided an idea of the capability of Taiwan’s MADS (a system in the PAC-3 family)
to defend against many incoming missiles. He told the Senate Foreign Relations
Committee that,
The PLA is expected to deploy substantial numbers of ballistic missiles which
could overcome a limited theater missile defense architecture. Assuming two
interceptors are dedicated against each incoming missile and a 100 percent
probability of kill, a Patriot-derived MADS battalion theoretically could halt a
near simultaneous barrage of 48 SRBMs directed against targets within the
battalion’s area of coverage. A 100 percent probability of kill, however, is not
likely. Larger SRBM salvos could ensure at least some ballistic missiles reach
their targets.61
Third, apparently because the legislative requirement called for architecture
requirements against limited ballistic missile attacks only, the DoD report did not
discuss the threat of PRC cruise missiles. The upper-tier missile defense systems
discussed in the DoD report as more effective options for Taiwan would not defend
61 U.S. Senate. Committee on Foreign Relations. Hearing on U.S.-Taiwan Relations: The
20th Anniversary of the Taiwan Relations Act. March 25, 1999.

CRS-27
against the PRC’s land-, air-, or ship-launched cruise missiles. The lower-tier PAC-3
system and MADS could provide some defense against cruise missiles.62 In February
1999, Taiwan’s Defense Minister Tang Fei warned that the PRC is stressing the
development of cruise missiles and has acquired Russian cruise missile technology
after 1996. Moreover, he reportedly said that the threat to Taiwan from cruise
missiles will eventually pose a greater threat than that of ballistic missiles.63 The
Secretary of Defense’s report on Taiwan security also confirmed that China is
developing land-attack cruise missiles (LACMs), with a “relatively high development
priority” and an “aggressive effort to acquire foreign cruise missile technology and
subsystems, particularly from Russia.” That DoD report on Taiwan security
predicted that the PRC’s first LACM to be produced will probably be air-launched
and could be operational early in the 21st century. Moreover, the PRC is improving
its C-801 and C-802 anti-ship cruise missiles (ASCMs). The report warned that the
PLA Navy could “saturate the Taiwan Navy with barrages of ASCMs.” The PLA is
planning to acquire Russian SS-N-22/Sunburn ASCMs deployed on two
Sovremenny-class destroyers. China is also expected to deploy submerged-launch
cruise missiles on its submarines, according to the Defense Secretary.64 The
warheads on the PRC’s cruise missiles may be conventional or carry WMD.
Fourth, the five missile defense options for Taiwan discussed in the DoD report
on missile defense in East Asia address only one aspect of missile defense.
According to DoD, TMD is comprised of four operational pillars: active defense,
passive defense, attack operations, and C4I (essential for any of the other pillars).65
As pointed out in the Defense Secretary’s report on Taiwan security, “exclusive
reliance on active missile defenses and associated BM/C3I [battle
management/command, control, communications, intelligence], however, will not
sufficiently offset the overwhelming advantage in offensive missiles which Beijing
is projected to possess in 2005.”66 Taiwan’s defense planners may prefer to develop
aspects of missile defense other than the active defense options discussed in the DoD
report on TMD. For example, there is reportedly growing support in Taiwan for the
development and deployment of ballistic missiles to deter Chinese missile attacks by
targeting the PRC’s major cities, such as Beijing and Shanghai, for retaliation.67
Similarly, the DoD report did not discuss other possible missile defense options such
as the Airborne Laser and Space-Based Laser (boost-phase intercept systems) that
could destroy the enemy missiles near their launch sites and associated structures.
62 BMDO.
63 Wu, Sofia, “Tang Fei Says PRC Cruise Missiles to Post Threat by 2005,” Taiwan Central
News Agency, February 9, 1999.
64 Secretary of Defense, “The Security Situation in the Taiwan Strait,” Report to Congress
Pursuant to the FY99 Appropriations Bill, February 1, 1999.
65 DoD, “Doctrine for Joint Theater Missile Defense,” Joint Pub 3-01.5, Feb. 22, 1996.
66 Secretary of Defense, “The Security Situation in the Taiwan Strait,” Report to Congress
Pursuant to the FY99 Appropriations Bill, February 1, 1999.
67 Opall-Rome, Barbara, “Support Mounts In Taiwan For Ballistic Missiles,” Defense News,
April 26, 1999.

CRS-28
Fifth, Taiwan may conclude that its pursuit of missile defense options (through
indigenous development, U.S. arms sales, or co-development) may be an inefficient
and expensive use of limited defense resources. For example, the unspecified ship-
position required in a sea-based upper-tier system could be provided by the U.S.
Navy, and not necessarily the Taiwan Navy. There may also be other options to
lessen cross-strait tensions, including dialogue and confidence-building measures,
provided Beijing is willing to pursue meaningful exchanges.
Political Considerations and U.S. Options
Arguments Against. While beyond the scope of the DoD report on TMD
options, there are political and security considerations concerning the possible
transfer of U.S. missile defense systems to Taiwan. Foremost, the PRC favors the
“one China” policy and objects to increases in U.S. arms sales to Taiwan, especially
those perceived to increase Taiwan’s potential offensive capability. The PRC
strenuously opposes U.S. TMD transfers to Taiwan as spurring its movement towards
independence by reestablishing close U.S. defense cooperation with Taiwan akin to
an alliance – a relationship that some say is more important for Taiwan’s defense
than simply acquiring weapon systems. The PRC also argues that missile defenses
in Asia would be destabilizing and would prompt the PRC to engage in an arms race
by responding with additional deployments of missiles. Some U.S. policymakers are
concerned about the negative impact on U.S.-PRC relations that would obstruct the
pursuit of important U.S. interests that require PRC cooperation, including improved
cross-strait relations, stability in Korea, weapon nonproliferation, and expanded U.S.
exports to China. Some are concerned about provoking the PRC with narrow
military solutions that derail efforts to improve cross-Strait relations which ultimately
provide Taiwan with lasting security. Finally, U.S.-Taiwan missile defense
cooperation could complicate critical U.S.-Japan cooperation in missile defense by
aggravating Chinese concerns about a U.S.-led coalition to contain China and any
possible Japanese links to Taiwan’s missile defense systems.
Arguments in Favor. Those in the United States and Taiwan who support
the potential deployment of missile defense systems in Taiwan point out that the PRC
already has been building up its offensive missile force in a destabilizing manner.
Facing such a real and growing threat, Taiwan needs to respond with TMD systems
as one way to improve its defenses against potential PRC intimidation and attacks.
Some are confident that the TMD systems proposed would significantly mitigate the
PRC missile threat. Along with missile defense systems, deepened military
cooperation with the United States would help to enhance Taiwan’s military
hardware as well as military thinking and training (software). Improved early
warning systems could improve stability in a potentially volatile situation and avoid
miscalculations. Taiwan’s acquisition of active defense systems may be preferable
to its possible pursuit of offensive missile systems for deterrence or even warfighting.
Some say that Taiwan’s defense is ultimately its responsibility, and its pursuit of
TMD systems is one way to shore up defenses. The Taiwan Relations Act (TRA)
(P.L. 96-8) requires that “the United States will make available to Taiwan such
defense articles and defense services in such quantity as may be necessary to enable
Taiwan to maintain a sufficient self-defense capability” (sec. 3(a)). In the summer
of 1999, Deputy Assistant Secretary of Defense Kurt Campbell testified to the Senate
Foreign Relations Committee that the TRA has been “the most successful piece of

CRS-29
legislative leadership in foreign policy in recent history.”68 In 1999, moreover, some
in Congress introduced the Taiwan Security Enhancement Act (S. 693, Helms; H.R.
1838, DeLay), specifically authorizing the President to sell TMD-related systems and
other items to Taiwan. (The International Relations Committee later amended the
House version, removing specific references to particular systems. The
Administration and others in Congress oppose the bill as unnecessary and
counterproductive, since it could jeopardize the current situation of maintaining
strong but unofficial ties to Taipei while pursuing engagement with Beijing.)
U.S. Options. Thus, U.S. policy has a broad range of options. The United
States could focus on development and deployment of TMD systems in Asia that
could cover Taiwan — without transfers of TMD systems or technology to Taiwan.
Such development and deployment may or may not involve allies, such as Japan.
Alternatively, the United States could sell one missile defense system or a
combination of TMD systems to Taiwan without technology transfers. On the other
hand, U.S. sales may include sharing related technology with Taiwan in co-
development and co-production. Finally, U.S. policy may examine the possible
development of other missile defense options in Taiwan in addition to the active
defense options discussed in the DoD report.
U.S. Considerations in Cooperative Missile Defense
Programs
Beyond the architecture requirements for establishing and operating missile
defenses for East Asia, there are numerous security, political, and economic issues
policy-makers might consider. A thorough discussion of these considerations was
beyond the scope of the DoD report. The topics will only be mentioned here to
indicate the complexity of the issue and possible implications of entering or
establishing a joint missile defense system.
! Associated with the acquisition of missile defense systems by Japan,
South Korea, or Taiwan would be improved protection of U.S.
troops and facilities abroad, and possibly a reduced call for U.S.
units to provide missile defense.
! Plans to establish a missile defense system could provoke hostilities
as North Korea or China saw its offensive military capability
eroding.
! If the allies were able to establish a very effective defense, it might
tend to dissuade North Korea and China from expanding their
missile forces because they would be of little use. However, a
marginally effective missile defense could encourage those countries
to increase their missile inventories and improve their missiles’
ability to penetrate defenses. Some analysts think North Korea and
68 Testimony before the Senate Foreign Relations Committee, Aug. 4, 1999.

CRS-30
China are determined to modernize their missile forces regardless of
allied defenses and that some level of arms race will continue in the
region.
! Cooperation in missile defense is seen as a sign of close security and
political relations between the United States and its three partners.
Many see these close relations as contributing to stability and peace
in the region, but China and North Korea perceive them as
hegemonic, threatening, and destabilizing. American analysts
disagree on the net political-military effects of East Asian missile
defenses, depending in part on the technical characteristics and
capabilities of the systems to be considered.
! Expending political capital and large sums of money on various
missile defense options may occur at the expense of other political
or military solutions that some analysts see as more effective.
! Cooperative missile defense provides an opportunity for Japan,
South Korea, and Taiwan to share technology and lucrative defense
contracts while sharing the economic burden of defending the
region. It has often been difficult for the United States to manage a
joint research and development program that is acceptable to all the
businesses and governments of participating countries.
! The transfer of cutting-edge missile defense technology to Japan,
South Korea, or Taiwan could have far-reaching implications for
their military and industrial capabilities that may or may not be in
the best interest of the United States, and could also violate U.S.
obligations under the ABM Treaty and the Missile Technology
Control Regime.

CRS-31
U.S. Options for Missile Defense in East Asia
The United States could pursue regional missile defense cooperation by sharing
any of a dozen systems, or any combination of them, with Japan, South Korea, or
Taiwan, or could deploy U.S. TMD systems in East Asia without their participation.
The DoD report discussed several of these missile defense options in terms of the
architecture requirements. The options considered by DoD are shaded in the table
below. Hypothetically, several other systems, including those associated with NMD,
might be shared with East Asia, although transfers may be constrained by the ABM
treaty or the Missile Technology Control Regime. Those options not considered in
the DoD report are not shaded in the table. Summarizing preceding discussions
above, the U.S. systems that might be shared include:
CLASS
SYSTEM
TARGET
Lower Tier
Land-Based
Patriot PAC-3
SRBMs in Terminal Phase,
Cruise Missiles
MEADS
SRBMs in Terminal Phase,
Cruise Missiles
Sea-Based
NAD
SRBMs in Terminal Phase,
Cruise Missiles
Upper Tier
Land-Based
THAAD
(Upper-Endo-
SRBMs, MRBMs, IRBMs with
Atmosphere,
an Apogee of 40+ km (25 mi.)
Exo-Atmosphere)
in Midcourse and Terminal
Phase
Sea-Based
NTW, Block I or II
SRBMs, MRBMs, IRBMs with
(Exo-Atmosphere)
altitude of 100+ km in Ascent,
Midcourse, or Exo-Descent
Phase
Boost Phase Intercept
Air-Based
Airborne Laser
Any Ballistic Missile within
several hundred km of aircraft
Space-Based
Space-based Laser
Any Ballistic Missile within
view of satellite
Air-Based
Unmanned Aerial
Any Ballistic Missile within
Vehicle with Interceptor
range (tens of km?)

CRS-32
CLASS
SYSTEM
TARGET
NMD
Land-Based
Similar to initial or
ICBMs +
augmented systems
planned for U.S.
Sea-Based
Augmented NTW
MRBMs, IRBMs, and ICBMs
(Endo-Atmosphere)
at high altitude
Space-Based
Similar to U.S. research
ICBMs +
program
Radar/Sensors/Electronics
Land-Based
Equipment associated
Sea-Based
with each U.S. system
Space-Based
Battle Man-
agement/C3
Providing missile defense for Japan, Korea, and Taiwan may take any of several
forms. The United States could interact with one, two, or all three of them in the
following ways:
! Unilaterally develop, produce, and deploy missile defense units with
U.S. troops, providing some missile defense for East Asia,
! Deploy some additional U.S. MD protection for allied and friendly
forces or cities,
! Provide allies and friends early warning of missile attacks (from
space-, sea-, air-, or land-based sensors),
! Sell U.S. MD systems to allies and friends,
! Sell components, materials, and technology to help allies and friends
develop MD, or to help them enhance units previously transferred,
! Co-develop and co-produce U.S. MD with allies and friends,
! Integrate U.S. and Asian MD systems for regional coverage,
! Integrate allies and friends or geographic areas into U.S. NMD,
! Sell, co-produce, or co-develop NMD with allies and friends.
As Congress considers the TMD architecture options discussed in the DoD
report, additional information on the capabilities of potentially hostile missile forces,
the specific capabilities of U.S. missile defense systems, and the advantages and
disadvantages of sharing missile defense systems through various mechanisms, may
be of interest.

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