Navy Aegis Ballistic Missile Defense (BMD)
Program: Background and Issues for Congress

Updated July 28, 2020
Congressional Research Service
https://crsreports.congress.gov
RL33745




Navy Aegis Ballistic Missile Defense (BMD) Program

Summary
The Aegis ballistic missile defense (BMD) program, which is carried out by the Missile Defense
Agency (MDA) and the Navy, gives Navy Aegis cruisers and destroyers a capability for
conducting BMD operations. BMD-capable Aegis ships operate in European waters to defend
Europe from potential ballistic missile attacks from countries such as Iran, and in in the Western
Pacific and the Persian Gulf to provide regional defense against potential ballistic missile attacks
from countries such as North Korea and Iran. Under the FY2021 budget submission, the number
of BMD-capable Navy Aegis ships is projected to increase from 48 at the end of FY2021 to 65 at
the end of FY2025.
The Aegis BMD program is funded mostly through MDA’s budget. The Navy’s budget provides
additional funding for BMD-related efforts. MDA’s proposed FY2021 budget requests a total of
$1,805.1 million (i.e., about $1.8 billion) in procurement and research and development funding
for Aegis BMD efforts, including funding for two Aegis Ashore sites in Poland and Romania.
MDA’s budget also includes operations and maintenance (O&M) and military construction
(MilCon) funding for the Aegis BMD program.
Issues for Congress regarding the Aegis BMD program include the following:
 whether to approve, reject, or modify MDA’s FY2021 funding procurement and
research and development funding requests for the program;
 delays in the delays in the delivery of new assets for the Aegis BMD program;
 required numbers of BMD-capable Aegis ships versus available numbers of
BMD-capable Aegis ships;
 the burden that BMD operations may be placing on the Navy’s fleet of Aegis
ships, and whether there are alternative ways to perform BMD missions now
performed by U.S. Navy Aegis ships, such as establishing more Aegis Ashore
sites;
 allied burden sharing—how allied contributions to regional BMD capabilities
and operations compare to U.S. naval contributions to overseas regional BMD
capabilities and operations;
 whether to convert the Aegis test facility in Hawaii into an operational land-based
Aegis BMD site;
 the potential for ship-based lasers, electromagnetic railguns (EMRGs), and
hypervelocity projectiles (HVPs) to contribute in coming years to Navy terminal-
phase BMD operations and the impact this might eventually have on required
numbers of ship-based BMD interceptor missiles; and
 technical risk and test and evaluation issues in the Aegis BMD program.

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Contents
Introduction ..................................................................................................................................... 1
Background ..................................................................................................................................... 1

Aegis Ships ............................................................................................................................... 1
Ticonderoga (CG-47) Class Aegis Cruisers ........................................................................ 1
Arleigh Burke (DDG-51) Class Aegis Destroyers .............................................................. 1
Aegis Ships in Allied Navies .............................................................................................. 2
Aegis BMD System................................................................................................................... 2
Versions and Capabilities of Aegis BMD System ............................................................... 2
Aegis BMD Interceptor Missiles ........................................................................................ 5
Aegis Ashore Sites .................................................................................................................... 6
Sites in Romania and Poland .............................................................................................. 6
USINDOPACOM Commander Desire for Site in Guam .................................................... 7
Numbers of BMD-Capable Aegis Ships ................................................................................... 7
BMD-Capable Aegis Destroyers Forward-Homeported in Spain ............................................. 8
Aegis BMD Development Philosophy and Flight Tests ............................................................ 8
Allied Participation and Interest in Aegis BMD Program ......................................................... 9
Japan ................................................................................................................................... 9
South Korea ...................................................................................................................... 10
Other Countries ................................................................................................................. 10

FY2021-FY2025 MDA Procurement and R&D Funding ....................................................... 10
Issues for Congress ......................................................................................................................... 11
FY2021 Funding Request ........................................................................................................ 11
Delays in Delivery of New Assets for Aegis BMD Program ................................................... 11
Required vs. Available Numbers of BMD-Capable Aegis Ships ............................................ 12
Burden of BMD Mission on U.S. Navy Aegis Ships .............................................................. 12
Allied Burden Sharing: U.S. vs. Allied Contributions to Regional BMD Capabilities........... 15
Conversion of Hawaii Aegis Test Site ..................................................................................... 16
Potential Contribution from Lasers, Railguns, and Guided Projectiles................................... 17
Technical Risk and Test and Evaluation Issues ....................................................................... 17

Legislative Activity for FY2021 .................................................................................................... 19
Summary of Action on FY2021 MDA Funding Request ........................................................ 19
FY2021 National Defense Authorization Act (H.R. 6395/S. 4049) ........................................ 20
House ................................................................................................................................ 20
Senate ................................................................................................................................ 20

FY2021 DOD Appropriations Act (H.R. 7617) ...................................................................... 23
House ................................................................................................................................ 23

Figures
Figure 1. GAO Summary of Capabilities of Aegis BMD System Variants ..................................... 3

Tables
Table 1. FY201-FY2025 MDA Procurement and R&D Funding for Aegis BMD Efforts ............. 11
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Table 2. Summary of Congressional Action on FY2021 MDA Funding Request ......................... 20

Table A-1. Aegis BMD Flight Tests From January 2002 to the Present ........................................ 25

Appendixes
Appendix A. Aegis BMD Flight Tests ........................................................................................... 24

Contacts
Author Information ........................................................................................................................ 27

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Navy Aegis Ballistic Missile Defense (BMD) Program

Introduction
This report provides background information and issues for Congress on the Aegis ballistic
missile defense (BMD) program, a program carried out by the Missile Defense Agency (MDA)
and the Navy that gives Navy Aegis cruisers and destroyers a capability for conducting BMD
operations. The issue for Congress is whether to approve, reject, or modify Department of
Defense (DOD) acquisition strategies and proposed funding levels for the Aegis BMD program.
Congress’s decisions on the Aegis BMD program could significantly affect U.S. BMD
capabilities and funding requirements, and the BMD-related industrial base.
For an overview of the strategic and budgetary context in which the Aegis BMD program may be
considered, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans:
Background and Issues for Congress
, by Ronald O'Rourke.
Background
Aegis Ships
All but three the Navy’s cruisers and destroyers are called Aegis ships because they are equipped
with the Aegis ship combat system—an integrated collection of sensors, computers, software,
displays, weapon launchers, and weapons named for the mythological shield that defended Zeus.
(The exceptions are the Navy’s three Zumwalt [DDG-1000] class destroyers, which are discussed
below.) The Aegis system was originally developed in the 1970s for defending ships against
aircraft, anti-ship cruise missiles (ASCMs), surface threats, and subsurface threats. The system
was first deployed by the Navy in 1983, and it has been updated many times since. The Navy’s
Aegis ships include Ticonderoga (CG-47) class cruisers and Arleigh Burke (DDG-51) class
destroyers.
Ticonderoga (CG-47) Class Aegis Cruisers
A total of 27 CG-47s (CGs 47 through 73) were procured for the Navy between FY1978 and
FY1988; the ships entered service between 1983 and 1994. The first five ships in the class (CGs
47 through 51), which were built to an earlier technical standard in certain respects, were judged
by the Navy to be too expensive to modernize and were removed from service in 2004-2005,
leaving 22 ships in operation (CGs 52 through 73).
Arleigh Burke (DDG-51) Class Aegis Destroyers1
A total of 62 DDG-51s were procured for the Navy between FY1985 and FY2005; the first
entered service in 1991 and the 62nd entered service in FY2012. The first 28 ships are known as
Flight I/II DDG-51s. The next 34 ships, known as Flight IIA DDG-51s, incorporate some design
changes, including the addition of a helicopter hangar.
No DDG-51s were procured in FY2006-FY2009. The Navy during this period instead procured
the three above-mentioned Zumwalt (DDG-1000) class destroyers. The DDG-1000 design does

1 For more on the DDG-51 program, see CRS Report RL32109, Navy DDG-51 and DDG-1000 Destroyer Programs:
Background and Issues for Congress
, by Ronald O'Rourke.
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not use the Aegis system and does not include a capability for conducting BMD operations. Navy
plans do not call for modifying the three DDG-1000s to make them BMD-capable.2
Procurement of DDG-51s resumed in FY2010, following procurement of the three Zumwalt-class
destroyers. A total of 23 DDG-51s have been procured from FY2010 through FY2020. DDG-51s
procured in FY2017 and subsequent years are being built to a new version of the DDG-51 design
called the Flight III version. The Flight III version is to be equipped with a new radar, called the
Air and Missile Defense Radar (AMDR) or the SPY-6 radar, that is more capable than the SPY-1
radar installed on all previous Aegis cruisers and destroyers.
Aegis Ships in Allied Navies
Sales of the Aegis system to allied countries began in the late 1980s. Allied countries that now
operate, are building, or are planning to build Aegis-equipped ships include Japan, South Korea,
Australia, Spain, and Norway.3 Most of Japan’s Aegis-equipped ships are currently BMD-
capable, and Japan plans to make all of them BMD-capable in coming years. The Aegis-equipped
ships operated by South Korea, Australia, Spain, and Norway are currently not BMD-capable.
Aegis BMD System4
Aegis ships are given a capability for conducting BMD operations by incorporating changes to
the Aegis system’s computers and software, and by arming the ships with BMD interceptor
missiles. In-service Aegis ships can be modified to become BMD-capable ships, and DDG-51s
procured in FY2010 and subsequent years are being built from the start with a BMD capability.
Versions and Capabilities of Aegis BMD System
Overview
The Aegis BMD system exists in several variants. Listed in chronological order of development
and deployment (and ascending level of capability), these include (but are not necessarily limited
to) the 3.6.X variant, the 4.0.3 variant, the 4.1 variant, the 4.2 variant, the 5.0 CU (Capability
Upgrade) variant, the 5.1 variant, and the 6.0 or 6.X variant. The BMD system variants correlate
with certain versions (i.e., baselines, or BLs) of the overall Aegis system, which have their own
numbering system. The more recent BMD variants, in addition to being able to address more
challenging BMD scenarios, give BMD-equipped ships a capability to simultaneously perform
both BMD operations against ballistic missiles and anti-air warfare (AAW) operations (aka air-
defense operations) against aircraft and anti-ship cruise missiles. Figure 1 provides a 2019
Government Accountability Office (GAO) summary of the capabilities of the newer BMD
variants and their correlation to Aegis system baselines.
The Aegis BMD system was originally designed primarily to intercept theater-range ballistic
missiles, meaning short-, medium-, and intermediate-range ballistic missiles (SRBMs, MRBMs,
and IRBMs, respectively). In addition to its capability for intercepting theater-range ballistic
missiles, detection and tracking data collected by the Aegis BMD system’s radar might be passed

2 For more on the DDG-1000 program, see CRS Report RL32109, Navy DDG-51 and DDG-1000 Destroyer Programs:
Background and Issues for Congress
, by Ronald O'Rourke.
3 The Norwegian ships are somewhat smaller than the other Aegis ships, and consequently carry a reduced-size version
of the Aegis system that includes a smaller, less-powerful version of the SPY-1 radar.
4 Unless stated otherwise, information in this section is taken from MDA briefings on the Aegis BMD program given to
CRS and CBO analysts on the MDA’s FY2019 and prior-year budget submissions.
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to other U.S. BMD systems that are designed to intercept intercontinental ballistic missiles
(ICBMs), which might support intercepts of ICBMs that are conducted by those other U.S. BMD
systems.
Figure 1. GAO Summary of Capabilities of Aegis BMD System Variants

Source: Government Accountability Office, Missile Defense[:] Delivery Delays Provide Opportunity for Increased
Testing to Better Understand Capability
, GAO-19-387, June 2019, Table 5 on p. 31.
Potential for Intercepting ICBMs
With the advent of the Aegis BMD system’s new SM-3 Block IIA interceptor (which is discussed
further in the next section), DOD is evaluating the potential for the Aegis BMD system to
intercept certain ICBMs. Section 1680 of the FY2018 National Defense Authorization Act (H.R.
2810/P.L. 115-91 of December 12, 2017) directed DOD to “conduct a test to evaluate and
demonstrate, if technologically feasible, the capability to defeat a simple intercontinental ballistic
missile threat using the standard missile 3 block IIA missile interceptor.” DOD’s January 2019
missile defense review report states the following:
The SM-3 Blk IIA interceptor is intended as part of the regional missile defense
architecture, but also has the potential to provide an important “underlay” to existing GBIs
[ground-based interceptors] for added protection against ICBM threats to the homeland.
This interceptor has the potential to offer an additional defensive capability to ease the
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burden on the GBI system and provide continuing protection for the U.S. homeland against
evolving rogue states’ long-range missile capabilities.
Congress has directed DoD to examine the feasibility of the SM-3 Blk IIA against an
ICBM-class target. MDA will test this SM-3 Blk IIA capability in 2020. Due to the
mobility of sea-based assets, this new underlay capability will be surged in a crisis or
conflict to further thicken defensive capabilities for the U.S. homeland. Land-based sites
in the United States with this SM-3 Blk IIA missile could also be pursued.5
A March 18, 2019, press report states the following:
The Pentagon plans a “first-of-its-kind” test of an unprecedented weapons capability to
intercept and destroy an enemy Intercontinental Ballistic Missile “ICBM”—from a Navy
ship at sea using a Standard Missile-3 Block IIA.
The concept, as articulated by Pentagon officials and cited briefly in this years’ DoD
“Missile Defense Review,” would be to use an advanced SM-3 IIA to “underlay” and assist
existing Ground-Based Interceptors (GBI), adding new dimensions to the current US
missile defense posture.…
The testing, Pentagon officials tell Warrior, is slated for as soon as next year. The
effectiveness and promise of the Raytheon-built SM-3 IIA shown in recent testing have
inspired Pentagon weapons developers to envision an even broader role for the weapon.
The missile is now “proven out,” US weapons developers say….
“The SM-3 IIA was not designed to take out ICBMs, but is showing great promise. This
would be in the upper range of its capability—so we are going to try,” the Pentagon official
told Warrior….
The SM-3 IIA’s size, range, speed and sensor technology, the thinking suggests, will enable
it to collide with and destroy enemy ICBMs toward the beginning or end of their flight
through space, where they are closer to the boundary of the earth’s atmosphere.
“The SM-3 IIA would not be able to hit an ICBM at a high altitude, but it can go outside
the earth’s atmosphere,” the Pentagon official said. “You want to hit it as far away as
possible because a nuke could go off.”6
A March 26, 2018, press report states the following:
[MDA] Director Lt. Gen. Sam Greaves said MDA “is evaluating the technical feasibility
of the capability of the SM-3 Block IIA missile, currently under development, against an
ICBM-class target.”
“If proven to be effective against an ICBM, this missile could add a layer of protection,
augmenting the currently deployed GMD [ground-based missile defense] system,” Greaves
said in written testimony submitted March 22 to the Senate Armed Services strategic forces
subcommittee. [Greaves] said MDA will conduct a demonstration of the SM-3 Block IIA
against an ICBM-like target by the end of 2020.”7

5 Department of Defense, Missile Defense Review 2019, released January 17, 2019, p. 55. David Axe, “The U.S.
Navy’s New Missile Defense Is a Bad Idea,” National Interest, January 17, 2019.
6 Kris Osborn, “US Missile Defense Breakthrough: Navy Ships to Destroy Enemy ICBMs,” Warrior Maven, March 18,
2019.
7 Jason Sherman, “MDA Exploring Potential of SM-3 Block IIA Against ICBM Threat,” Inside the Navy, March 26,
2018. See also Jason Sherman, “MDA Charts New Technical Course and Test fort Aegis Homeland Defense,” Inside
Defense
, April 1, 2019; Rebeccah L. Heinrichs, “Let’s See If the SM-3 Block IIA Can Hit an ICBM,” Real Clear
Defense
, September 6, 2019.
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An April 22, 2020, press report states:
A top Defense Department official on Tuesday [April 21] said the department expects to
conduct a Standard Missile-3 (SM-3) Block IIA flight test against an intercontinental
ballistic missile (ICBM)-representative threat this summer….
“To further mitigate the risk in the interim period, we’re going to be looking at conducting
a test of the SM-3 Block IIA missile against a North Korean-representative ICBM
threat…and we’ll be doing that probably in the summer timeframe,” Deputy Assistant
Secretary of Defense for Nuclear and Missile Defense Policy Robert Soofer said during a
Hudson Institute video event.8
Aegis BMD Interceptor Missiles
The BMD interceptor missiles used by Aegis ships are the Standard Missile-3 (SM-3), the SM-2
Block IV, and the SM-6.
SM-3 Midcourse Interceptor
The SM-3 is designed to intercept ballistic missiles above the atmosphere (i.e., exo-atmospheric
intercept), in the midcourse phase of an enemy ballistic missile’s flight. It is equipped with a “hit-
to-kill” warhead, called a kinetic vehicle, that is designed to destroy a ballistic missile’s warhead
by colliding with it. MDA and Navy plans call for fielding increasingly capable versions of the
SM-3 in coming years. The current versions, called the SM-3 Block IA and SM-3 Block IB, are to
be supplemented in coming years by SM-3 Block IIA.
Compared to the Block IA version, the Block IB version has an improved (two-color) target
seeker, an advanced signal processor, and an improved divert/attitude control system for adjusting
its course. Compared to the Block IA and 1B versions, which have a 21-inch-diameter booster
stage at the bottom but are 13.5 inches in diameter along the remainder of their lengths, the Block
IIA version has a 21-inch diameter along its entire length. The increase in diameter to a uniform
21 inches provides more room for rocket fuel, permitting the Block IIA version to have a burnout
velocity (a maximum velocity, reached at the time the propulsion stack burns out) that is greater
than that of the Block IA and IB versions, as well as a larger-diameter kinetic warhead. The
United States and Japan have cooperated in developing certain technologies for the Block IIA
version, with Japan funding a significant share of the effort.9 A March 31, 2020, press report
stated:
Raytheon and the Missile Defense Agency are exploring options to extend the range of the
Standard Missile-3 Block IB—pushing the ballistic missile interceptor to dramatically
expand a defended area by allowing the weapon to communicate with off-board radars—a

8 Rich Abott, “SM-3 IIA ICBM Test Expected This Summer,” Defense Daily, April 22, 2020.
9 The cooperative research effort has been carried out under a U.S.-Japan memorandum of agreement signed in 1999.
The effort has focused on risk reduction for four parts of the missile: the sensor, an advanced kinetic warhead, the
second-stage propulsion, and a lightweight nose cone. The Block IIA development effort includes the development of a
missile, called the Block II, as a stepping stone to the Block IIA. As a result, the Block IIA development effort has
sometimes been called the Block II/IIA development effort. The Block II missile is not planned as a fielded capability.
MDA and Navy plans at one point called for the SM-3 Block IIA to be succeeded by a still more capable interceptor
called the SM-3 Block IIB. The effort to develop that missile, however, was ended, and MDA reportedly is not
pursuing any follow-on capabilities to the SM-3 Block IIA. (See, for example, Justin Doubleday, “Missile Defense
Agency Not Pursuing Follow-On to SM-3 Block IIA Interceptor,” Inside the Navy, October 24, 2016.)
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move that would require enhancing one of the Aegis ballistic missile defense system's
newest features: Engage-on-Remote….
MDA Director Vice Adm. Jon Hill told Congress earlier this month that the new Engage-
on-Remote capability provides “a seven-fold increase in missile defense coverage when
compared to an autonomous Aegis platform.”10
SM-2 and SM-6 Terminal Interceptors
The SM-2 Block IV is designed to intercept ballistic missiles inside the atmosphere (i.e., endo-
atmospheric intercept), during the terminal phase of an enemy ballistic missile’s flight. It is
equipped with a blast fragmentation warhead. The existing inventory of SM-2 Block IVs—72 as
of February 2012—was created by modifying SM-2s that were originally built to intercept
aircraft and ASCMs. A total of 75 SM-2 Block IVs were modified, and at least 3 were used in
BMD flight tests.
MDA and the Navy are now procuring a more-capable terminal-phase (endo-atmospheric
intercept) BMD interceptor based on the SM-6 air defense missile (the successor to the SM-2 air
defense missile). The SM-6 is a dual-capability missile that can be used for either air defense (i.e.,
countering aircraft and anti-ship cruise missiles) or ballistic missile defense. A July 23, 2018,
press report states the following:
The Defense Department has launched a prototype project that aims to dramatically
increase the speed and range of the Navy’s Standard Missile-6 by adding a larger rocket
motor to the ship-launched weapon, a move that aims to improve both the offensive and
defensive reach of the Raytheon-built system.
On Jan. 17, the Navy approved plans to develop a Dual Thrust Rocket Motor with a 21-
inch diameter for the SM-6, which is currently fielded with a 13.5-inch propulsion package.
The new rocket motor would sit atop the current 21-inch booster, producing a new variant
of the missile: the SM-6 Block IB.11
Aegis Ashore Sites
Sites in Romania and Poland
On September 17, 2009, the Obama Administration announced a new approach for regional BMD
operations called the Phased Adaptive Approach (PAA). The first application of the approach is in
Europe, and is called the European Phased Adaptive Approach (EPAA). EPAA calls for using
BMD-capable Aegis ships, a land-based radar in Europe, and two Aegis Ashore sites in Romania
and Poland to defend Europe against ballistic missile threats from countries such as Iran.
Phase I of EPAA involved deploying Aegis BMD ships and a land-based radar in Europe by the
end of 2011. Phase II involved establishing the Aegis Ashore site in Romania with SM-3 IB
interceptors in 2016.12 Phase 3 involves establishing the Aegis Ashore site in Poland with SM-3

10 Jason Sherman, “After MDA Demonstrates 7x Increase in Defended Area, Raytheon Pitching EOR for Older SM-
3s,” Inside Defense, March 31, 2020.
11 Jason Sherman, “Navy Looking to Increase Range, Speed of SM-6 with Larger Rocket Motor,” Inside the Navy, July
23, 2018.
12 The Aegis Ashore site in Romania was operationally certified on May 12, 2016. (See “Aegis Ashore Missile Defense
System-Romania Operationally Certified, Navy News Service, May 12, 2016; Sam LaGrone, “Aegis Ashore Site in
Romania Declared Operational,” USNI News, May 12, 2016.)
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IIA interceptors. The completion of construction of the Poland site has been delayed by four
years, to 2022, due to construction contractor performance issues.13 Each Aegis Ashore site in the
EPAA is to include a structure housing an Aegis system similar to the deckhouse on an Aegis ship
and 24 SM-3 missiles launched from a relocatable Vertical Launch System (VLS) based on the
VLS that is installed in Navy Aegis ships.14
Although BMD-capable Aegis ships were deployed to European waters before 2011, the first
BMD-capable Aegis ship officially deployed to European waters as part of the EPAA departed its
home port of Norfolk, VA, on March 7, 2011, for a deployment to the Mediterranean that lasted
several months.15
USINDOPACOM Commander Desire for Site in Guam
A July 21, 2020, press report stated:
The head of U.S. Indo-Pacific Command told reporters today he wants the Aegis Ashore
ballistic missile defense system to bolster the defense of Guam from Chinese missiles.
The Aegis Ashore Baseline 10 system should be “the backbone of [a] homeland defense
system” for Guam, Adm. Phil Davidson said during a Defense Writers Group virtual
roundtable.
“The reason I’m a key advocate for that is first: it is technology that is available to us now
and could be delivered by 2026, when I believe the threat will require us to have a much
more robust capability than the combination of [Terminal High Altitude Area Defense],
which is deployed there now, and an Aegis ship in response can provide,” Davidson said.
Davidson said the current defense system for Guam is not adequate to thwart potential
Chinese missiles.
“When you look at the way the threat capability, threat capacity, is manifesting from China
in the future—whether it’s ballistic missiles from the land or whether it’s ballistic or cruise
missiles from air and maritime platforms—you are going to need a complete clock, a 360-
degree coverage in order to help defend Guam,” the admiral said.16
Numbers of BMD-Capable Aegis Ships
Under the FY2021 budget submission, the number of BMD-capable Navy Aegis ships is
projected to increase from 48 at the end of FY2021 to 65 at the end of FY2025. The portion of the

13 See, for example, Rich Abott, “Delayed Poland Aegis Ashore Site Needs Two More Years,” Defense Daily, February
12, 2020; Jen Judson, “Poland’s Aegis Ashore Delayed to 2022 with New Way Forward Coming Soon,” Defense News,
February 18, 2020; Megan Eckstein, “MDA, Army Withholding Pay as Aegis Ashore Poland Construction Still
Drags,” USNI News, March 12, 2020.
14 For additional discussion of the Aegis Ashore sites, see Edward Lundquist, “Aegis Ashore Adapts Sea-Based Missile
Defense System to Protect Europe,” National Defense, September 2016.
15 Karen Parrish, “Milestone nears for European Missile Defense Plan,” American Forces Press Service, March 2, 2011
(http://archive.defense.gov/news/newsarticle.aspx?id=62997); Untitled “Eye On The Fleet” news item, Navy News
Service
, March 7, 2011 (accessed online at http://www.navy.mil/view_single.asp?id=98184); “Warship With Radar
Going To Mediterranean,” Washington Post, March 2, 2011; Brock Vergakis, “US Warship Deploys to Mediterranean
to Protect Europe Form Ballistic Missiles, Canadian Press, March 7, 2011.
16 Mallory Shelbourne, “Protecting Guam from Chinese Missiles is Top Priority for INDO-PACOM’s Davidson,”
USNI News, July 21, 2020. See also Mandy Mayfield, “Web Exclusive: Commander Wants Aegis Ashore Funding to
Defend Guam,” National Defense, July 21, 2020, and Aaron Mehta, “INDOPACOM Head Wants Aegis Ashore in
Guam by 2026,” Defense News, July 22, 2020.
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force equipped with earlier Aegis variants is decreasing, and the number equipped with later
variants is increasing.
BMD-Capable Aegis Destroyers Forward-Homeported in Spain
On October 5, 2011, the United States, Spain, and NATO jointly announced that, as part of the
EPAA, four BMD-capable U.S. Navy Aegis destroyers were to be forward-homeported (i.e.,
based) at the naval base at Rota, Spain.17 The four ships were transferred to Rota in FY2014 and
FY2015.18 They are reportedly scheduled to return to the United States and replaced at Rota by a
new set of four BMD-capable U.S. Navy Aegis destroyers in 2020-2022.19 Navy officials have
said that the four Rota-based ships can provide a level of level of presence in the Mediterranean
for performing BMD patrols and other missions equivalent to what could be provided by about 10
BMD-capable Aegis ships that are homeported on the U.S. east coast. The Rota homeporting
arrangement thus effectively releases about six U.S. Navy BMD-capable Aegis ships for
performing BMD patrols or other missions elsewhere.
In February and March 2020, DOD officials testified that DOD is considering forward-
homeporting an additional two BMD-capable Aegis destroyers at Rota, which would make for a
total of ships at the site.20 Navy officials have testified that they support the idea.21
Aegis BMD Development Philosophy and Flight Tests
The Aegis BMD development effort, including Aegis BMD flight tests, has been described as
following a development philosophy long held within the Aegis program office of “build a little,
test a little, learn a lot,” meaning that development is done in manageable steps, then tested and
validated before moving on to the next step.22 For a summary of Aegis BMD flight tests since
2002, see Appendix A.

17 “Announcement on missile defence cooperation by NATO Secretary General Anders Fogh Rasmussen, the Prime
Minister of Spain, Jose Luis Rodriguez Zapatero and US Defense Secretary Leon Panetta,” October 5, 2011, accessed
October 6, 2011, at http://www.nato.int/cps/en/SID-107ADE55-FF83A6B8/natolive/opinions_78838.htm. See also
“SECDEF Announces Stationing of Aegis Ships at Rota, Spain,” accessed October 6, 2011, at http://www.navy.mil/
search/display.asp?story_id=63109.
Rota is on the southwestern Atlantic coast of Spain, a few miles northwest of Cadiz, and about 65 miles northwest of
the Strait of Gibraltar leading into the Mediterranean. U.S. Navy ships have been homeported at Rota at various points
in the past, most recently (prior to the current arrangement) in 1979. (Source: Sam Fellman, “U.S. To Base Anti-
Missile Ships in Spain,” Defense News, October 10, 2011: 76.)
18 The four ships are the destroyers Ross (DDG-71) and Donald Cook (DDG-75), which moved to Rota in FY2014, and
the destroyers Carney (DDG-64) and Porter (DDG-78), which moved to Rota in FY2015.
19 See, for example, Sam LaGrone, “Navy to Station Advanced Warships, Helo Squadron in Spain,” USNI News, June
5, 2019; Rich Abott, “Navy Cycling Four New Missile Defense Destroyers To Spain,” Defense Daily, June 7, 2019.
20 See, for example, Paul McCleary, “EUCOM Calls For Two More Ships For Spanish Port,” Breaking Defense,
February 25, 2020; David B. Larter, “Push to Base Six US Navy Destroyers in Spain Could Be Gaining Steam,”
Defense News, March 3, 2020.
21 See, for example, David B. Larter, “The US Navy’s Top Officer Declares Support for Basing 6 Destroyers in Spain,”
Defense News, March 5, 2020.
22 See, for example, “Aegis BMD: “Build a Little, Test a Little, Learn a Lot,” USNI blog, March 15, 2010, accessed
September 11, 2013, at http://blog.usni.org/2010/03/15/aegis-bmd-build-a-little-test-a-little-learn-a-lot, and “Aegis
Ballistic Missile Defense, Aegis Ballistic Missile Defense Overview for the George C. Marshall Institute, RADM Alan
B. Hicks, USN, Aegis BMD Program Director, August 3, 2009, slide 16 of 20, entitled “Some of our Philosophies In a
Nutshell (1 of 2),” accessed September 11, 2011, at http://www.marshall.org/pdf/materials/743.pdf.
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Allied Participation and Interest in Aegis BMD Program
Japan23
Eight BMD-Capable Aegis Destroyers
Japan plans to operate a force of eight BMD-capable Aegis destroyers. Seven of the ships are in
service. In June, it was reported that the eighth ship had started sea trials and is scheduled to enter
service in 2021.24 Japanese BMD-capable Aegis ships have participated in some of the flight tests
of the Aegis BMD system using the SM-3 interceptor (see Table A-1 in Appendix A).
Cooperative Development of SM-3 Block IIA Missile
Japan cooperated with the United States on development the SM-3 Block IIA missile. Japan
developed certain technologies for the missile, and paid for the development of those
technologies, reducing the missile’s development costs for the United States. A July 6, 2018,
press report states that “the U.S. and Japan are looking to jointly develop next-generation radar
technology that would use Japanese semiconductors to more than double the detection range of
the Aegis missile defense system.”25
Two Aegis Ashore Sites (Canceled)
Japan had planned to procure and operate two Aegis Ashore systems that reportedly were to be
located at Ground Self-Defense Force (GSDF) facilities in Akita Prefecture in eastern Japan and
Yamaguchi Prefecture in western Japan, and would be operated mainly by the GSDF (i.e., Japan’s
army).26 The two systems reportedly were to be equipped with a new Lockheed-made radar called
the Long Range Discrimination Radar (LRDR) rather than the Raytheon-made SPY-6 AMDR that
is being installed on U.S. Navy Flight III DDG-51s, and reportedly were to go into operation by
2023.27
On June 15, 2020, however, Japan announced that it had suspended implementation of its Aegis
Ashore initiative due to cost growth and technical concerns.28 On June 18, 2020, it was reported

23 For a research paper providing additional background information U.S.-Japan cooperation in ballistic missile
defense, see Rachel Hoff, “U.S.-Japan Missile Defense Cooperation: Increasing Security and Cutting Costs,” American
Action Forum, December 2, 2015.
24 Mike Yeo, “Japan’s New Missile Defense Destroyer Starts Sea Trials amid Aegis Ashore Saga,” Defense News, June
23, 2020.
25 Nikkei staff writers, “US Taps Japan Radar Tech to Double Missile Defense Range,” Nikkei Asian Review, July 6,
2018.
26 Yomiuri Shimbun, “Akita, Yamaguchi to Get Aegis Ashore/GSDF Involvement Expected to Strengthen Missile
Defense,” The Japan News, November 11, 2017. See also Kyodo, “Japan Mulling News Missile Interceptor
Deployment to Guard Against North Korea,” South China Morning Post, November 11, 2017.
27 Anthony Capaccio, “Japan in Talks With U.S. on Buying Aegis Missile Defense,” Bloomberg, November 7, 2017.
28 See, for example, Rich Abott, “Japan Suspends Aegis Ashore Due To Technical And Cost Concerns,” Defense Daily,
June 15, 2020; Sam LaGrone, “Japan Backing Away From Aegis Ashore,” USNI News, June 15, 2020; Mari
Yamaguchi, “Japan to Scrap Costly Land-Based US Missile Defense System,” Associated Press, June 15, 2020; Mike
Yeo, “Japan Suspends Aegis Ashore Deployment, Pointing to Cost and Technical Issues,” Defense News, June 15,
2020; Brad Glosserman, “Canceling Aegis Ashore Raises Problems—and Hopes,” Japan Times, June 17, 2020.
Prior to the June 15, 2020, announcement, Japan had announced in early May that it would evaluate alternatives to the
Akita Prefecture site due to strong local opposition to that site. (Masaya Kato, “Japan’s Missile Shield Deployment
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that the United States and Japan were in talks to address the technical issues Japan cited and
explore potential paths forward for bolstering Japan’s ballistic missile defense capability.29 On
June 25, 2020, Japan confirmed that it had canceled the plan for deploying the two Aegis Ashore
sites.30 On July 10, 2020, it was reported that Japan might reverse its decision and reinstate a
program to deploy Aegis Ashore sites.31
South Korea
An October 12, 2018, press report states that “the South Korean military has decided to buy ship-
based SM-3 interceptors to thwart potential ballistic missile attacks from North Korea, a top
commander of the Joint Chiefs of Staff revealed Oct. 12.32
Other Countries
Other countries that MDA views as potential naval BMD operators (using either the Aegis BMD
system or some other system of their own design) include the United Kingdom, the Netherlands,
Spain, Germany, Denmark, and Australia. Spain, South Korea, and Australia either operate, are
building, or are planning to build Aegis ships. The other countries operate destroyers and frigates
with different combat systems that may have potential for contributing to BMD operations.
FY2021-FY2025 MDA Procurement and R&D Funding
The Aegis BMD program is funded mostly through MDA’s budget. The Navy’s budget provides
additional funding for BMD-related efforts. Table 1 shows FY2021-FY2025 MDA procurement
and research and development funding for Aegis BMD efforts. Research and development
funding for the land-based SM-3 is funding for Aegis Ashore sites. MDA’s budget also includes
additional funding not shown in the table for operations and maintenance (O&M) and military
construction (MilCon) for the Aegis BMD program.

Scuppered by Local Resistance,” Nikkei Asian Review, May 7, 2020.)
29 Lara Seligman, “U.S. and Japan in Talks about ‘Alternatives’ to Aegis Ashore Missile Defense System,” Politico
Pro
, June 18, 2020; Idrees Ali, “U.S. in Talks with Japan after Aegis Ashore Missile Defense System Suspension:
Official,” Reuters, June 18, 2020; Jason Sherman, “MDA Hopes to ‘Resolve’ Japan’s Aegis Ashore Concerns,
Reinstate Project,” Inside Defense, June 18, 2020; “U.S. Talking with Japan on Concerns over Halted Missile Defense
Plan,” Kyodo News, June 19, 2020.
30 Mari Yamaguchi (Associated Press), “Japan Confirms It’s Scrapping US Missile Defense System,” Defense News,
June 25, 2020; Megan Eckstein, “Japan Officially Ends Aegis Ashore Plans After National Security Council
Deliberations,” USNI News, June 26, 2020. See also Grant Newsham “Abe’s Aegis Ashore Cancellation Doesn’t Add
Up,” Asia Times, June 30, 2020; Lucy Craft, “Why Japan Scrapped a $4 Billion Missile Defense Purchase from the
U.S.,” CBS News, July 2, 2020; Tim Kelly, “Explainer: Strike Capability, Other Military Options on Table after Japan’s
Aegis U-Turn,” Reuters, July 2, 2020; Jeffrey W. Hornung, “Japan Is Canceling a U.S. Missile Defense System,”
Foreign Policy, July 2, 2020; Bruce Klingner, “Japan Undercuts Its Defense Against North Korean Missiles,” Heritage
Foundation, July 22, 2020.
31 Tim Kelly, “Exclusive: Japan May Still build Aegis Ashore Despite Reports of Cancellation, Source Says,” Reuters,
July 10, 2020.
32 Jeff Jeong, “South Korea to Buy Ship-Based Interceptors to Counter Ballistic Missile Threats,” Defense News,
October 12, 2018.
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Table 1. FY201-FY2025 MDA Procurement and R&D Funding for Aegis BMD Efforts
(In millions of dollars, rounded to nearest tenth; totals may not add due to rounding)

FY21
FY22
FY23
FY24
FY25

(req.)
(proj.)
(proj.)
(proj.)
(proj.)
Procurement






Aegis BMD (line 34)

356.2
348.1
413.4
440.9
438.6
(SM-3 Block IB missile quantity)

(34)
(35)
(41)
(34)
(33)
Aegis BMD Advance Procurement (line 35)

44.9
17.5
0
0
0
SM-3 Block IIA (line 37)

218.3
131.9
127.0
1,180.1
1,108.2
(SM-3 Block IIA missile quantity)

(6)
(3)
(3)
(51)
(50)
Aegis Ashore Phase III (line 40)

39.1
26.2
3.9
2.4
1.0
Aegis BMD hardware and software (line 42)

104.2
109.2
103.2
126.0
124.5
SUBTOTAL Procurement

762.7
632.9
647.5 1,749.4 1,744.3
Research and development






Aegis BMD (PE 0603892C) (line 82)

814.9
674.8
553.4
478.0
449.1
Aegis BMD Test (PE 0604878C) (line 113)

170.9
191.7
163.1
179.9
217.7
Land-based SM-3 (PE 0604880C) (line 115)

56.6
43.7
29.1
31.5
27.9
SUBTOTAL RDT&E

1,042.4
910.2
745.6
689.4
694.7
TOTAL

1,805.1
1,543.1 1,393.1 2,438.8 2,439.0
Source: Table prepared by CRS based on FY2021 MDA budget submission.
Issues for Congress
FY2021 Funding Request
One issue for Congress is whether to approve, reject, or modify MDA’s FY2021 procurement and
research and development funding requests for the program. In considering this issue, Congress
may consider various factors, including whether the work that MDA is proposing to fund for
FY2021 is properly scheduled for FY2021, and whether this work is accurately priced.
Delays in Delivery of New Assets for Aegis BMD Program
Another issue for Congress concerns delays in the delivery of new assets for the Aegis BMD
program. A June 2019 GAO report on BMD program delivery delays states:
The Aegis BMD SM-3 Block IB program, which received full production authority early
in fiscal year 2018 after years of delays, delivered 12 of 36 planned interceptors in fiscal
year 2018. This shortfall was due to the discovery of a parts quality issue that necessitated
suspending deliveries until MDA could complete an investigation of the issue’s impact on
the interceptor’s performance. In addition, the Aegis BMD SM-3 Block IIA program
delivered one of four planned test interceptors due to a flight test failure early in the year
suspending further deliveries pending completion of a failure review board.
Moreover, according to MDA officials, construction contractor performance issues will
result in the Aegis Ashore Missile Defense System Complex—Poland not being delivered
until at least 18 months after the planned December 2018 date.… [T]his facility is central
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to MDA’s plans for the EPAA Phase 3, such that a delay in the completion of this facility
resulted in a delay in the planned EPAA Phase 3 delivery to the warfighter.33
Required vs. Available Numbers of BMD-Capable Aegis Ships
Another potential issue for Congress concerns required numbers of BMD-capable Aegis ships
versus available numbers of BMD-capable Aegis ships. Some observers are concerned about the
potential operational implications of a shortfall in the available number of BMD-capable relative
to the required number. Regarding the required number of BMD-capable Aegis ships, an August
15, 2018, Navy information paper states the following:
The [Navy’s] 2016 Force Structure Assessment [FSA]34 sets the requirement [for BMD-
capable ships] at 54 BMD-capable ships, as part of the 104 large surface combatant
requirement, to meet Navy unique requirements to support defense of the sea base and
limited expeditionary land base sites….
The minimum requirement for 54 BMD ships is based on the Navy unique requirement as
follows. It accepts risk in the sourcing of combatant commander (CCDR) requests for
defense of land.
- 30 to meet CVN escort demand for rotational deployment of the carrier strike groups
- 11 INCONUS for independent BMD deployment demand
- 9 in forward deployed naval forces (FDNF) Japan to meet operational timelines in
USINDOPACOM
- 4 in FDNF Europe for rotational deployment in EUCOM.35
Burden of BMD Mission on U.S. Navy Aegis Ships
A related potential issue for Congress is the burden that BMD operations may be placing on the
Navy’s fleet of Aegis ships, particularly since performing BMD patrols requires those ships to
operate in geographic locations that may be unsuitable for performing other U.S. Navy missions,
and whether there are alternative ways to perform BMD missions now performed by U.S. Navy
Aegis ships, such as establishing more Aegis Ashore sites. A June 16, 2018, press report states the
following:
The U.S. Navy’s top officer wants to end standing ballistic missile defense patrols and
transfer the mission to shore-based assets.
Chief of Naval Operations Adm. John Richardson said in no uncertain terms on June 12
that he wants the Navy off the tether of ballistic missile defense patrols, a mission that has
put a growing strain on the Navy’s hard-worn surface combatants, and the duty shifted
towards more shore-based infrastructure.
“Right now, as we speak, I have six multi-mission, very sophisticated, dynamic cruisers
and destroyers―six of them are on ballistic missile defense duty at sea,” Richardson said

33 Government Accountability Office, Missile Defense[:] Delivery Delays Provide Opportunity for Increased Testing to
Better Understand Capability
, GAO-19-387, June 2019, p. 13. The GAO report provides further discussion of these
delays on pages 18, 22-26, 34-36, 38-39, and 42-43.
34 The FSA is the Navy’s analysis, performed every few years, that establishes the Navy’s ship force structure
requirements. For further discussion, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans:
Background and Issues for Congress
, by Ronald O'Rourke.
35 Navy information paper dated August 15, 2018, entitled “Ballistic Missile Defense (BMD) Capable Ships
requirement,” provided by Navy Office of Legislative Affairs to CBO and CRS on August 15, 2018. The information
paper was requested by CBO.
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during his address at the U.S. Naval War College’s Current Strategy Forum. “And if you
know a little bit about this business you know that geometry is a tyrant.
“You have to be in a tiny little box to have a chance at intercepting that incoming missile.
So, we have six ships that could go anywhere in the world, at flank speed, in a tiny little
box, defending land.”
Richardson continued, saying the Navy could be used in emergencies but that in the long
term the problem demands a different solution.
“It’s a pretty good capability and if there is an emergent need to provide ballistic missile
defense, we’re there,” he said. “But 10 years down the road, it’s time to build something
on land to defend the land. Whether that’s AEGIS ashore or whatever, I want to get out of
the long-term missile defense business and move to dynamic missile defense.”
The unusually direct comments from the CNO come amid growing frustration among the
surface warfare community that the mission, which requires ships to stay in a steaming box
doing figure-eights for weeks on end, is eating up assets and operational availability that
could be better used confronting growing high-end threats from China and Russia.
The BMD mission was also a factor in degraded readiness in the surface fleet. Amid the
nuclear threat from North Korea, the BMD mission began eating more and more of the
readiness generated in the Japan-based U.S. 7th Fleet, which created a pressurized situation
that caused leaders in the Pacific to cut corners and sacrifice training time for their crews,
an environment described in the Navy’s comprehensive review into the two collisions that
claimed the lives of 17 sailors in the disastrous summer of 2017.
Richardson said that as potential enemies double down on anti-access technologies
designed to keep the U.S. Navy at bay, the Navy needed to focus on missile defense for its
own assets.
“We’re going to need missile defense at sea as we kind of fight our way now into the battle
spaces we need to get into,” he said. “And so restoring dynamic maneuver has something
to do with missile defense.36
A June 23, 2018, press report states the following:
The threats from a resurgent Russia and rising China―which is cranking out ships like it’s
preparing for war―have put enormous pressure on the now-aging [U.S. Navy Aegis
destroyer] fleet. Standing requirements for BMD patrols have put increasing strain on the
U.S. Navy’s surface ships.
The Navy now stands at a crossroads. BMD, while a burden, has also been a cash cow that
has pushed the capabilities of the fleet exponentially forward over the past decade. The
game-changing SPY-6 air and missile defense radar destined for DDG Flight III, for
example, is a direct response to the need for more advanced BMD shooters. But a smaller
fleet, needed for everything from anti-submarine patrols to freedom-of-navigation missions
in the South China Sea, routinely has a large chunk tethered to BMD missions.
“Right now, as we speak, I have six multimission, very sophisticated, dynamic cruisers and
destroyers―six of them are on ballistic missile defense duty at sea,” Chief of Naval
Operations Adm. John Richardson said during an address at the recent U.S. Naval War
College’s Current Strategy Forum. “You have to be in a tiny little box to have a chance at
intercepting that incoming missile. So we have six ships that could go anywhere in the
world, at flank speed, in a tiny little box, defending land.”

36 David B. Larter, “The US Navy Is Fed Up with Ballistic Missile Defense Patrols,” Defense News, June 16, 2018. See
also Paul McLeary, “Will Budget Crunch Pentagon Laser & Space Investments?” Breaking Defense, November 13,
2018.
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And for every six ships the Navy has deployed in a standing mission, it means 18 ships are
in various stages of the deployment cycle preparing to relieve them.
The Pentagon, led by Defense Secretary Jim Mattis, wants the Navy to be more flexible
and less predictable―“dynamic” is the buzzword of moment in Navy circles. What
Richardson is proposing is moving standing requirements for BMD patrols away from
ships underway and all the associated costs that incurs, and toward fixed, shore-based sites,
and also surging the Navy’s at-sea BMD capabilities when there is an active threat....
In a follow-up response to questions posed on the CNO’s comments, Navy spokesman
Cmdr. William Speaks said the Navy’s position is that BMD is an integral part of the
service’s mission, but where long-term threats exist, the Navy should “consider a more
persistent, land-based solution as an option.”
“This idea is not about the nation’s or the Navy’s commitment to BMD for the U.S. and
our allies and partners―the Navy’s commitment to ballistic missile defense is rock-solid,”
Speaks said. “In fact, the Navy will grow the number of BMD-capable ships from 38 to 60
by 2023, in response to the growing demand for this capability.
“The idea is about how to best meet that commitment. In alignment with our national
strategic documents, we have shifted our focus in an era of great power competition―this
calls us to think innovatively about how best to meet the demands of this mission and
optimize the power of the joint force.”...
While the idea of saving money by having fixed BMD sites and freeing up multimission
ships is sensible, it may have unintended consequences, said Bryan McGrath, a retired
destroyer skipper and owner of the defense consultancy The FerryBridge Group.
“The BMD mission is part of what creates the force structure requirement for large surface
combatants,” McGrath said on Twitter after Defense News reported the CNO’s comments.
“Absent it, the number of CG’s and DDG’s would necessarily decline. This may in fact be
desirable, depending on the emerging fleet architecture and the roles and missions debate
underway. Perhaps we need more smaller, multi-mission ships than larger, more expensive
ones.
“But it cannot be forgotten that while the mission is somewhat wasteful of a capable, multi-
mission ship, the fact that we have built the ships that (among other things) do this mission
is an incredibly good thing. If there is a penalty to be paid in peacetime sub-optimization
in order to have wartime capacity—should this not be considered a positive thing?”
McGrath went on to say that the suite of combat systems that have been built into Aegis
have been in response to the BMD threat. And indeed, the crown jewels of the surface
fleet―Aegis Baseline 9 software, which allows a ship to do both air defense and BMD
simultaneously; the Aegis common-source library; the forthcoming SPY-6; cooperative
engagement―have come about either in part or entirely driven by the BMD mission....
A Navy official who spoke on condition of anonymity, to discuss the Navy’s shifting
language on BMD, acknowledged the tone had shifted since the 2000s when the Navy
latched onto the mission. But the official added that the situation more than a decade later
has dramatically shifted.
“The strategic environment has changed significantly since the early 2000s―particularly
in the western Pacific. We have never before faced multiple peer rivals in a world as
interconnected and interdependent as we do today,” the official said. “Nor have we ever
seen technologies that could alter the character of war as dramatically as those we see
emerging around us. China and Russia have observed our way of war and are on the move
to reshape the environment to their favor.”
In response to the threat and Defense Secretary Jim Mattis’ desire to use the force more
dynamically, the Navy is looking at its options, the official said. “This includes taking a
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look at how we employ BMD ships through the lens of great power competition to compete,
deter and win against those who threaten us.”37
A January 29, 2019, press report states the following:
The Navy is looking to get out of the missile defense business, the service’s top admiral
said today, and the Pentagon’s new missile defense review might give the service the off-
ramp it has been looking for to stop sailing in circles waiting for ground-based missile
launches.
This wasn’t the first time Adm. John Richardson bristled in public over his ships sailing in
“small boxes” at sea tasked with protecting land, when they could be out performing other
missions challenging Chinese and Russian adventurism in the South China Sea and the
North Atlantic….
“We’ve got exquisite capability, but we’ve had ships protecting some pretty static assets
on land for a decade,” Richardson said at the Brookings Institute. “If that [stationary] asset
is going to be a long-term protected asset, then let’s build something on land and protect
that and liberate these ships from this mission.”
Japan is already moving down the path of building up a more robust ground-based sensor
and shooter layer, while also getting its own ships out to sea armed with the Aegis radar
and missile defense system, both of which would free up American hulls from what
Richardson on Monday called “the small [geographic] boxes where they have to stay for
ballistic missile defense.”38
Allied Burden Sharing: U.S. vs. Allied Contributions to Regional
BMD Capabilities
Another related potential issue for Congress concerns allied burden sharing—how allied
contributions to regional BMD capabilities and operations compare to U.S. naval contributions to
overseas regional BMD capabilities and operations, particularly in light of constraints on U.S.
defense spending, worldwide operational demands for U.S. Navy Aegis ships, and calls by some
U.S. observers for increased allied defense efforts. The issue can arise in connection with both
U.S. allies in Europe and U.S. allies in Asia. Regarding U.S. allies in Asia, a December 12, 2018,
press report states the following:
In June, US Navy Chief of Naval Operations (CNO) Admiral John Richardson said during
a speech at the US Naval War College that the US Navy should terminate its current
practice of dedicating several US Navy warships solely for Ballistic Missile Defense
(BMD).
Richardson wanted US warships to halt BMD patrols off Japan and Europe as they are
limiting, restrictive missions that could be better accomplished by existing land-based
BMD systems such as Patriot anti-missile batteries, the US Terminal High Altitude Area
Defense (THAAD) anti-missile system and the Aegis Ashore anti-missile system.
In the months since dropping his bombshell, Richardson—and much of the debate—has
gone quiet.
“My guess is the CNO got snapped back by the Pentagon for exceeding where the debate
actually stood,” one expert on US naval affairs told Asia Times.

37 David B. Larter, “As Threats Mount, US Navy Grapples with Costly Ballistic Missile Defense Mission,” Defense
News
, June 23, 2018.
38 Paul McLeary, “The Navy Has Had Enough of Missile Defense And Sees Its Chance,” Breaking Defense, January
28, 2019.
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But others agree with him. Air Force Lt Gen Samuel A Greaves, the director of the US
Missile Defense Agency (MDA), acknowledges Richardson’s attempts to highlight how
these BMD patrols were placing unwelcome “strain on the (US Navy’s) crews and
equipment.”
But there are complications. While it may free US Navy warships for sea-control, rather
than land defense, there is a concern that next- generation hypersonic cruise missiles could
defeat land-based BMD systems, such as Aegis Ashore, while the US Navy’s Aegis-
equipped warships offer the advantages of high-speed mobility and stealth, resulting in
greater survivability overall.
As Japan prepares to acquire its first Aegis Ashore BMD system – and perhaps other
systems such as the THAAD system which has been deployed previously in Romania and
South Korea – the possibility that the US Navy will end its important BMD role represents
abrupt change….
Japan’s decision to deploy Aegis Ashore can fill in any gap created by a possible US Navy
cessation of BMD patrols. “The land-based option is more reliable, less logistically
draining, and despite being horrendously expensive, could be effective in the sense that it
provides a degree of reassurance to the Japanese people and US government, and
introduces an element of doubt of missile efficacy into [North Korean] calculations,” said
[Garren Mulloy, Associate Professor of International Relations at Daito Bunka University
in Saitama, Japan], adding, however, that these systems could not cover Okinawa.
“Fixed sites in Japan could be vulnerable, and the Aegis vessels provide a flexible forward-
defense, before anything enters Japanese airspace, but with obviously limited reactions
times,” Mulloy said. “Aegis Ashore gives more reaction time – but over Japanese
airspace.”…
The silence about this sudden possible shift in the US defense posture in the western Pacific
is understandable: it is a sensitive topic in Washington and Tokyo. However, the Trump
administration has urged its allies to pay more for their own defense needs and to support
US troops deployed overseas.
Meanwhile, Tokyo needs to proceed cautiously given the likelihood that neighbors might
view a move on BMD as evidence that Tokyo is adopting an increasingly aggressive
defense posture in the region.
But for them, it is a no-win situation. If the US does ditch the BMD patrol mission, China
and North Korea might view the shift as equally menacing given that it greatly enhances
the US Navy’s maritime warfare capabilities.39
Conversion of Hawaii Aegis Test Site
Another potential issue for Congress is whether to convert the Aegis test facility in Hawaii into an
operational land-based Aegis BMD site. DOD’s January 2019 missile defense review report
states, in a section on improving or adapting existing BMD systems, that
Another repurposing option is to operationalize, either temporarily or permanently, the
Aegis Ashore Missile Defense Test Center in Kauai, Hawaii, to strengthen the defense of
Hawaii against North Korean missile capabilities. DoD will study this possibility to further
evaluate it as a viable near-term option to enhance the defense of Hawaii. The United States
will augment the defense of Hawaii in order to stay ahead of any possible North Korean
missile threat. MDA and the Navy will evaluate the viability of this option and develop an
Emergency Activation Plan that would enable the Secretary of Defense to operationalize
the Aegis Ashore test site in Kauai within 30 days of the Secretary’s decision to do so, the

39 Peter J. Brown, “Japan, US Silent over Ending Ballistic Missile Patrols,” Asia Times, December 12, 2018.
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steps that would need to be taken, associated costs, and personnel requirements. This plan
will be delivered to USDA&S, USDR&E, and USDP within six months of the release of
the MDR.40
A January 25, 2019, press report states the following:
The Defense Department will examine the funding breakdown between the Navy and the
Missile Defense Agency should the government make Hawaii’s Aegis Ashore Missile
Defense Test Center into an operational resource, according to the agency’s director.
“Today, it involves both Navy resources for the operational crews—that man that site—as
well as funds that come to MDA for research, development and test production and
sustainment,” Lt. Gen. Sam Greaves said of the test center when asked how the funding
would shake out between the Navy and MDA should the Pentagon move forward with the
recommendation.41
Potential Contribution from Lasers, Railguns, and Guided
Projectiles
Another potential issue for Congress concerns the potential for ship-based lasers, electromagnetic
railguns (EMRGs), and gun-launched guided projectiles (GLGPs, previously known as
hypervelocity projectiles [HVPs]) to contribute in coming years to Navy terminal-phase BMD
operations and the impact this might eventually have on required numbers of ship-based BMD
interceptor missiles. Another CRS report discusses the potential value of ship-based lasers,
EMRGs, and GLGPs for performing various missions, including, potentially, terminal-phase
BMD operations.42
Technical Risk and Test and Evaluation Issues
Another potential oversight issue for Congress is technical risk and test and evaluation issues in
the Aegis BMD program. Regarding this issue, a December 2019 report from DOD’s Director,
Operational Test and Evaluation (DOT&E)—DOT&E’s annual report for FY2019—stated the
following in its section on the Aegis BMD program:
Assessment
• Results from flight testing, high-fidelity M&S [modeling and simulation], and HWIL
[hardware-in-the-loop] testing demonstrate that Aegis BMD can intercept non‑separating,
simple-separating, and complex-separating ballistic missiles in the midcourse phase of
flight. However, flight testing and M&S did not address all expected threat types, ground
ranges, and raid sizes.
• [Flight test] FTM-45 demonstrated that Aegis destroyers can organically engage and
intercept MRBMs with SM-3 Block IIA missiles. [Flight test] FTI-03 demonstrated, for
the first time in an end-to-end test, Aegis BMD’s capability to intercept an IRBM using
EOR [engage-on-remote capability] and an SM-3 Block IIA missile.
• OPTEVFOR [the Navy Commander, Operational Test and Evaluation Force] accredited
Aegis BMD high-fidelity M&S tools for many scenarios, but it noted limitations for raid

40 Department of Defense, Missile Defense Review 2019, released January 17, 2019, pp. 55-56.
41 Mallory Shelbourne, “DOD to Determine Funding Breakdown for Aegis Ashore Repurposing,” Inside the Navy,
January 25, 2019.
42 See CRS Report R44175, Navy Lasers, Railgun, and Gun-Launched Guided Projectile: Background and Issues for
Congress
, by Ronald O'Rourke.
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engagements due to the lack of validation data from live fire raid engagements and lack of
post-intercept debris modeling.
• During the four events that comprised FS-19 [Formidable Shield-19], the MDA
demonstrated Aegis BMD interoperability with NATO partners over the U.S. European
Command Operational Tactical Data Link communication architecture during cruise
missile and ballistic missile engagements. An Aegis destroyer twice engaged a simulated
MRBM target with live SM-3 Block IA missiles, performed engagement support
surveillance and track, organically engaged a live SRBM target with a simulated SM-6
Block 1 guided missile, and organically engaged a lofted SRBM target with simulated SM-
3 Block IB (Threat Update) missiles. During the last engagement, the geo-repositioned
AAMDTC [Aegis Ashore Missile Defense Test Complex] launched a simulated SM-3
Block IIA guided missile at the target, using track data from the BL [Baseline] 9.C2 ship
in an EOR scenario.
• Aegis BMD has exercised rudimentary engagement coordination with Terminal High-
Altitude Area Defense [THAAD] firing units, but not with Patriot. MDA ground tests have
routinely shown that inter-element coordination and interoperability need improvement to
enhance engagement efficiency.
• The MDA has been collaborating with DOT&E and the USD(R&E) [Under Secretary of
Defense, Research and Engineering] to establish an affordable ground testing approach to
support assessments of reliability. DOT&E cannot assess SM-3 missile reliability with
confidence until the MDA is able to provide additional ground test data that simulates the
in-flight environment. In FY19, the MDA identified possible data sources to inform
reliability estimates, but the data will not be available until CY21 [calendar year 2021].
• A December 2017 SM-3 Block IB Acquisition Decision Memorandum [ADM] requires
the MDA and DOT&E to ensure periodic flight testing of the Block IB throughout the life
of the program in the Integrated Master Test Plan. DOT&E and the MDA agreed that
periodic testing would occur at approximately 2 year intervals. The MDA conducted two
surveillance firings of the SM-3 Block IB missile in FY18, and two Stockpile Surveillance
and Reliability program firings of the SM-3 Block IA missile in FY19.
• AN/SPY-6(V)1 [radar, aka Air and Missile Defense Radar, or AMDR] participated in its
final Navy-funded BMD developmental test, FTX-34. This tracking exercise was the last
of five SPY-6(V)1 BMD tracking exercises at the U.S. Navy's Advanced Radar
Development Evaluation Laboratory (ARDEL). ARDEL does not have the most recent
Aegis combat system (i.e., BL [baseline] 10), precluding future integration testing with the
AN/SPY-6 radar at that facility.
Recommendations
The MDA should:
1. Provide data from high-fidelity ground test venues in the near term to help inform SM-
3 Block IB Threat Upgrade and Block IIA missile reliability estimates.
2. Continue to conduct periodic (approximately every 2 years) SM-3 Block IB firings
throughout the life of the program to demonstrate missile reliability.
3. Conduct Aegis BMD flight testing with live fire intercepts of raids of two or more
ballistic missile targets to aid in the validation of M&S tools for raid engagements.
4. Improve Aegis BMD high-fidelity M&S tools to incorporate post-intercept debris
modeling to better assess engagement performance in raid scenarios.
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5. Coordinate with the Navy to fund an Aegis BL10 combat system at ARDEL for use in
future combat system integration testing with the AN/SPY-6 radar.43
Regarding the SM-6 missile, the December 2019 DOT&E report also stated the following:
Assessment
• As reported in the FY18 DOT&E SM-6 BLK I FOT&E Report, the SM-6 remains
effective and suitable with the exception of the classified deficiency identified in the FY13
IOT&E [Initial Operational Test and Evaluation] Report. The SM-6 BLK I satisfactorily
demonstrated compatibility with AWS [Aegis Weapon System] Baseline 9 Integrated Fire
Control capability.
• The Navy is not planning operational testing or lethality assessments for SM-6 BLK I
and BLK IA FCD [Future Capabilities Demonstration]. The FCD represent significant
warfighting improvements for Aegis destroyers and cruisers. DOT&E, with the Navy’s
concurrence, actively participated in the planning and execution of the FY19 and planned
future developmental test events, and will report, as appropriate, on these warfighting
enhancements.
• Data analysis is underway on the completed SM-6 BLK IA live fire and M&S FOT&E
events. DOT&E will report on SM-6 BLK 1A FOT&E [Follow-On Operational Test and
Evaluation] in FY20.
Recommendations
The Navy should:
1. Continue to improve software based on results investigating the classified performance
deficiency discovered during IOT&E, perform corrective actions, and verify corrective
actions with flight tests. This includes correcting the two new problems identified during
FY17 SM-6 BLK I Verification of Corrected Deficiency tests.
2. Plan FOT&E testing and lethality assessments for SM-6 BLK I and BLK IA FCD.44
Legislative Activity for FY2021
Summary of Action on FY2021 MDA Funding Request
Table 2
summarizes congressional action on the FY2021 request for MDA procurement and
research and development funding for the Aegis BMD program.

43 Department of Defense, Director, Operational Test & Evaluation, FY2019 Annual Report, December 20, 2019, pp.
216-217.
44 Department of Defense, Director, Operational Test & Evaluation, FY2019 Annual Report, December 20, 2019, pp.
163-164.
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Table 2. Summary of Congressional Action on FY2021 MDA Funding Request
(In millions of dollars, rounded to nearest tenth; totals may not add due to rounding)
Authorization
Appropriation

Request
HASC
SASC
Conf.
HAC
SAC
Conf.
Procurement
Aegis BMD (line 34)
356.2
356.2
356.2

356.2


(SM-3 Block IB missile quantity)
(34)
(34)
(34)

(34)


Aegis BMD Advance Procurement (line 35)
44.9
44.9
44.9

44.9


SM-3 Block IIA (line 37)
218.3
333.3
346.3

318.3


(SM-3 Block IIA missile quantity)
(6)
(10)
(11)

(6+)


Aegis Ashore Phase III (line 40)
39.1
39.1
39.1

34.6


Aegis BMD hardware and software (line 42)
104.2
104.2
104.2

104.2


Subtotal Procurement
762.7
877.7
890.7

858.1


Research, development, test, and evaluation (RDT&E)
Aegis BMD (PE 0603892C) (line 82)
814.9
804.9
814.9

771.3


Aegis BMD test (PE 0604878C) (line 113)
170.9
95.9
170.9

139.3


Land-based SM-3 (PE 0604880C) (line 115)
56.6
56.6
133.4

56.6


Subtotal RDT&E
1,042.4
957.4 1,119.2

967.2


TOTAL
1,805.1 1,835.1 2,009.9

1,825.3


Source: Table prepared by CRS based on DOD’s original FY2021 budget submission, committee and
conference reports, and explanatory statements on FY2021 National Defense Authorization Act and FY2021
DOD Appropriations Act.
Notes: HASC is House Armed Services Committee; SASC is Senate Armed Services Committee; HAC is
House Appropriations Committee; SAC is Senate Appropriations Committee; Conf. is conference agreement.
FY2021 National Defense Authorization Act (H.R. 6395/S. 4049)
House
The House Armed Services Committee, in its report (H.Rept. 116-442 of July 9, 2020) on H.R.
6395, recommended the funding levels shown in the HASC column of Table 2. The
recommended increase of $115.0 million for line 37 is for “Increase SM–3 Block IIA quantities.”
(Page 366) The recommended reduction of $10.0 million for line 82 is for “Program decrease.”
(Pages 415-416) The recommended reduction of $75.0 million for line 113 is for “Unjustified
cost growth.” (Page 417)
Senate
The Senate Armed Services Committee, in its report (S.Rept. 116-236 of June 24, 2020) on S.
4049, recommended the funding levels shown in the SASC column of Table 2. The
recommended increase of $128.0 million for line 37 is for “Additional SM–3 Block IIA
interceptors.” (Page 478) The recommended increase of $76.8 million for line 115 is for “PDI
[Pacific Deterrence Initiative]: Guam Defense System—systems engineering.” (Page 529)
Regarding the recommended funding level for line 37, S.Rept. 116-236 states:
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SM–3 IIA procurement
The budget request included $218.3 million in line number 37 of Procurement, Defense-
Wide (PDW), for SM–3 Block IIA missiles.
The committee believes that procuring higher quantities of this interceptor each year
(including foreign military sales) is prudent, given existing requirements for Aegis Ashore
and Aegis Ballistic Missile Defense ships, the capacity and efficiencies of the industrial
base, and the potential for additional land-based SM–3 systems. The committee also notes
that this increased procurement was included on the unfunded priorities list submitted by
the Director of the Missile Defense Agency.
Accordingly, the committee recommends an increase of $128.0 million in line number 37
of PDW for SM–3 Block IIA missiles. (Pages 40-41)
Regarding the recommended funding level for line 115, S.Rept. 116-236 states:
PDI: Guam Defense System
The budget request did not include funding in Research, Defense, Test, and Evaluation
(RDT&E), Defense-wide, for PE 64880C Land-Based SM–3 for a Guam Defense System
(GDS).
The committee notes that this project was included on the unfunded priorities list submitted
by the Commander, U.S. Indo-Pacific Command, who stated that Guam is both the
western-most territory of the U.S. homeland and a critical location for posture and
operations in the Indo-Pacific area of responsibility. The committee agrees with the
Commander that protection of U.S. assets and personnel on Guam is critical for effective
operations in the region.
Accordingly, the committee recommends an increase of $76.8 million in RDT&E,
Defense-wide, for PE 64880C Land-Based SM–3 for GDS.
In addition, the committee expects the Missile Defense Agency (MDA), along with U.S.
Strategic Command (STRATCOM) and U.S. Indo-Pacific Command (INDOPACOM), to
continue to analyze and refine the plan for a defense architecture against the range of
missile threats to Guam while also beginning the work described above.
Accordingly, not later than January 31, 2021, the committee directs the Secretary of
Defense, in consultation with the Director of the MDA and the Commanders, STRATCOM
and INDOPACOM, to submit to the congressional defense committees an assessment of
the architecture required for the defense of Guam from air and missile threats, including
ballistic, hypersonic, and cruise missiles. The assessment shall include the following
elements:
(1) An analysis of existing and projected air and missile threats to U.S. forces, assets, and
infrastructure located on Guam;
(2) An analysis of impacts to the ability of U.S. forces to conduct operations in the
INDOPACOM area of operations if systems and assets on Guam are vulnerable to air and
missile threats;
(3) An analysis of systems currently available for procurement or deployment that could
contribute to the defense of Guam from these threats not later than the end of 2025;
(4) An analysis of new systems currently in development, or modifications to existing
systems, that could enhance or substitute for existing options in contributing to this
mission;
(5) Estimated cost and schedule for the various options studied; and
(6) Anything else the Secretary deems relevant. (Page 119)
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Section 1664 of S. 4049 as reported by the committee states (emphasis added):
SEC. 1664. REPORT ON AND LIMITATION ON EXPENDITURE OF FUNDS FOR
LAYERED HOMELAND MISSILE DEFENSE SYSTEM.
(a) REPORT REQUIRED.—
(1) IN GENERAL.—Not later than March 1, 2021, the Director of the Missile Defense
Agency shall submit to the congressional defense committees
a report on the proposal for a layered homeland missile defense system included in the
budget justification materials submitted to Congress in support of the budget for the
Department of Defense for fiscal year 2021 (as submitted with the budget of the President
for such year under section 1105(a) of title 31, United States Code).
(2) ELEMENTS REQUIRED.—The report required by paragraph (1) shall include the
following:
(A) A description of the approved requirements for a layered homeland missile defense
system, based on an assessment by the intelligence community of threats to be addressed
at the time of deployment of such a system.
(B) An assessment of how such requirements addressed by a layered homeland missile
defense system relate to those addressed by the existing ground-based midcourse defense
system, including deployed ground-based interceptors and planned upgrades to such
ground based interceptors.
(C) An analysis of interceptor solutions to meet such requirements, to include land-
based Standard Missile 3 (SM–3) Block IIA interceptor systems
and the Terminal High
Altitude Area Defense (THAAD) system, with the number of locations required for
deployment and the production numbers of interceptors and related sensors.
(D) A site-specific fielding plan that includes possible locations, the number and type of
interceptors and radars in each location, and any associated environmental or permitting
considerations, including an assessment of the locations evaluated pursuant to section
227(b) of the National Defense Authorization Act for Fiscal Year 2013 (126 Stat. 1679;
Public Law 112–239) for inclusion in the layered homeland missile defense system.
(E) Relevant policy considerations for deployment of such systems for defense against
intercontinental ballistic missiles in the continental United States.
(F) A cost estimate and schedule for options involving a land-based Standard Missile 3
Block IIA interceptor system and the Terminal High Altitude Area Defense system,
including required environmental assessments.
(G) A feasibility assessment of the necessary modifications to the Terminal High Altitude
Area Defense system to address such requirements.
(H) An assessment of the industrial base capacity to support additional production of either
a land-based Standard Missile 3 Block IIA interceptor system or the Terminal High
Altitude Area Defense system.
(3) CONSULTATION.—In preparing the report required by paragraph (1), the Director
shall consult with the following:
(A) The Under Secretary of Defense for Policy.
(B) The Under Secretary of Defense for Acquisition and Sustainment.
(C) The Vice Chairman of the Joint Chiefs of Staff, in Vice Chairman’s capacity as the
Chair of the Joint Requirements Oversight Council.
(D) The Commander, United States Strategic Command.
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(E) The Commander, United States Northern Command.
(b) LIMITATION ON USE OF FUNDS.—Not more than 50 percent of the amounts
authorized to be appropriated by this Act for fiscal year 2021 for the Missile Defense
Agency for the purposes of a layered homeland missile defense system may be obligated
or expended until the Director submits to the congressional defense committees the report
required by subsection (a).
(c) INTELLIGENCE COMMUNITY DEFINED.—In this section, the term ‘‘intelligence
community’’ has the meaning given such term in section 3 of the National Security Act of
1947 (50 U.S.C. 3003).
Regarding Section 1664, S.Rept. 116-236 states:
Report on and limitation on expenditure of funds for layered homeland missile
defense system (sec. 1664)

The committee recommends a provision that would require the Director of the Missile
Defense Agency (MDA) to submit a report to the congressional defense committees no
later than March 1, 2021, on the layered homeland missile defense system proposed in the
President’s fiscal year 2021 budget request. The report would include cost estimates,
schedule options, requirements, and an analysis of possible architecture solutions, in
addition to relevant policy considerations. The provision would prohibit the obligation or
expenditure of more than 50 percent of fiscal year 2021 funds authorized for this purpose
until the required report is submitted.
The committee supports the Department of Defense’s efforts to seek additional homeland
missile defense coverage in the mid-2020s; however, the committee notes that the
Department has provided very little information or analysis to support this proposal, despite
including substantial funding within the MDA budget for this purpose. The $260.0 million
as requested is authorized elsewhere in this Act. (Page 353)
FY2021 DOD Appropriations Act (H.R. 7617)
House
The House Appropriations Committee, in its report (H.Rept. 116-453 of July 16, 2020) on H.R.
7617, recommended the funding levels shown in the HAC column of Table 2. The recommended
increase of $100.0 million for line 37 is for “Program increase—additional SM-3 Block IIA
interceptors.” (Page 232) The recommended reduction of $4.485 million for line 40 is for “Excess
growth.” (Page 232) The recommended reductions of $43.6 million for line 82 and $31.537
million for line 113 are for “Excess growth.” (Page 314)


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Appendix A. Aegis BMD Flight Tests
Table A-1
presents a summary of Aegis BMD flight tests since January 2002. As shown in the
table, since January 2002, the Aegis BMD system has achieved 33 successful exo-atmospheric
intercepts in 42 attempts using the SM-3 missile (including 4 successful intercepts in 5 attempts
by Japanese Aegis ships, and 2 successful intercepts in 3 attempts attempt using the Aegis Ashore
system), and 7 successful endo-atmospheric intercepts in 7 attempts using the SM-2 Block IV and
SM-6 missiles, making for a combined total of 40 successful intercepts in 49 attempts.
In addition, on February 20, 2008, a BMD-capable Aegis cruiser operating northwest of Hawaii
used a modified version of the Aegis BMD system with the SM-3 missile to shoot down an
inoperable U.S. surveillance satellite that was in a deteriorating orbit. Including this intercept in
the count increases the totals to 34 successful exo-atmospheric intercepts in 43 attempts using the
SM-3 missile, and 41 successful exo- and endo-atmospheric intercepts in 50 attempts using SM-
3, SM-2 Block IV, and SM-6 missiles.


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Table A-1. Aegis BMD Flight Tests From January 2002 to the Present
Name of flight
Cumulative Cumulative
Date
Country
test of exercise
Ballistic Missile Target
Successful?
successes
attempts
Exo-atmospheric (using SM-3 missile)
1/25/02
US
FM-2
Unitary short-range (TTV)
Yes
1
1
6/13/02
US
FM-3
Unitary short-range (TTV)
Yes
2
2
11/21/02
US
FM-4
Unitary short-range (TTV)
Yes
3
3
6/18/03
US
FM-5
Unitary short-range (TTV)
No
3
4
12/11/03
US
FM-6
Unitary short-range (TTV)
Yes
4
5
2/24/05
US
FTM 04-1 (FM-7)
Unitary short-range (TTV)
Yes
5
6
11/17/05
US
FTM 04-2 (FM-8)
Separating short-range (MRT)
Yes
6
7
6/22/06
US
FTM 10
Separating short-range (TTV)
Yes
7
8
12/7/06
US
FTM 11
Unitary short-range (TTV)
No
7
9
4/26/07
US
FTM 11
Unitary short-range (ARAV-A)
Yes
8
10
Event 4
6/22/07
US
FTM 12
Separating short-range (MRT)
Yes
9
11
8/31/07
US
FTM-11a
Classified
Yes
10
12
11/6/07
US
FTM 13
Unitary short-range (ARAV-A)
Yes
11
13


Unitary short-range (ARAV-A)
Yes
12
14
12/17/07
Japan
JFTM-1
Separating short-range (MRT)
Yes
13
15
11/1/08
US
Pacific Blitz
Unitary short-range (ARAV-A)
Yes
14
16


Unitary short-range (ARAV-A)
No
14
17
11/19/08
Japan
JFTM-2
Separating short-range (MRT)
No
14
18
7/30/09
US
FTM-17
Unitary short-range (ARAV-A)
Yes
15
19
10/27/09
Japan
JFTM-3
Separating short-range (MRT)
Yes
16
20
10/28/10
Japan
JFTM-4
Separating short-range (MRT)
Yes
17
21
4/14/11
US
FTM-15
Separating intermediate range (LV-
Yes
18
22
2)
9/1/11
US
FTM-16 E2
Separating short-range (ARAV-B)
No
18
23
5/9/12
US
FTM-16 E2a
Unitary short-range (ARAV-A)
Yes
19
24
6/26/12
US
FTM-18
Separating short-range (MRT)
Yes
20
25
10/25/12
US
FTI-01
Separating short-range (ARAV-B)
No
20
26
2/12/13
US
FTM-20
Separating medium-range (MRBM-
Yes
21
27
T3)
5/15/13
US
FTM-19
Separating short-range (ARAV-C)
Yes
22
28
9/10/13
US
FTO-01
Separating medium-range
Yes
23
29
(eMRBM-T1)
9/18/13
US
FTM-21
Separating short-range (ARAV-
Yes
24
30
C++)
10/3/13
US
FTM-22
Separating medium-range (ARAV-
Yes
25
31
TTO-E)
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Name of flight
Cumulative Cumulative
Date
Country
test of exercise
Ballistic Missile Target
Successful?
successes
attempts
11/6/14
US
FTM-25
Separating short-range (ARAV-B)
Yes
26
32
6/25/15
US
FTO-02 E1
Separating medium-range (IRBM
n/aa
26
32
T1)
10/4/15
US
FTO-02 E2
Separating medium-range
n/ac
26
32
(eMRBM)
10/20/15
US
ASD-15 E2
Separating short-range (Terrier
Yes
27
33
Orion)
11/1/15
US
FTO-02 E2a
Separating medium-range
No
27
34
(eMRBM)
12/10/15
US (Aegis
FTO02 E1a
Separating medium-range (IRBM
Yes
28
35
Ashore)
T1)
2/3/17
US-Japan
SFTM-01
Separating medium-range (MRT)
Yes
29
36
6/21/17
US-Japan
SFTM-02
Medium-range
No
29
37
10/15/17
US
FS17
Medium-range target
Yes
30
38
1/31/18
US (Aegis
FTM-29
Intermediate-range target
No
30
39
Ashore)
9/11/18
Japan
JFTM-05
Simple separating target
Yes
31
40
10/26/18
US
FTM-45
Medium range
Yes
32
41
12/10/18
US (Aegis
FTI-03
Intermediate-range target
Yes
33
42
Ashore)
Endo-atmospheric (using SM-2 missile Block IV missile and [for MMW Event 1] SM-6 Dual 1 missile)
5/24/06
US
Pacific Phoenix
Unitary short-range target (Lance)
Yes
1
1
6/5/08
US
FTM-14
Unitary short-range target (FMA)
Yes
2
2
3/26/09
US
Stellar Daggers
Unitary short-range target (Lance)
Yes
3
3
7/28/15
US
MMW E1
Unitary short-range target (Lance)
Yes
4
4
7/29/15
US
MMW E2
Unitary short-range target (Lance)
Yes
5
5
12/14/16
US
FTM-27
Unitary short-range target (Lance)
Yes
6
6
8/29/17
US
FTM-27 E2
Medium-range target (MRBM)
Yes
7
7
Combined total for exo- and endo-atmospheric above tests
40
49
Sources: Table presented in MDA fact sheet, “Aegis Ballistic Missile Defense Testing,” February 2017, accessed
on October 16, 2017, at https://www.mda.mil/global/documents/pdf/aegis_tests.pdf, and (for flight tests
subsequent to February 2017) MDA news releases.
Notes: TTV is target test vehicle; ARAV is Aegis Readiness Assessment Vehicle. In addition to the flight tests
shown above, there was a successful use of an SM-3 on February 20, 2008, to intercept an inoperative U.S.
satellite—an operation called Burnt Frost. Including this intercept in the count increases the totals to 31
successful exo-atmospheric intercepts in 40 attempts using the SM-3 missile, and 38 successful exo- and endo-
atmospheric intercepts in 47 attempts using SM-3, SM-2 Block IV, and SM-6 missiles.
a. MDA’s table shows this as a test that did not result in the launch of an SM-3. MDA as of August 3, 2015,
had not issued a news release discussing this event. MDA’s count of 31 successful intercepts in 37 launches
through July 29, 2015, does not appear to include this test, suggesting that this was considered a “no test”
event—a test in which there was a failure that was not related to the Aegis BMD system or the SM-3
interceptor. News reports state that the test was aborted due to a failure of the target missile. (Andrea
Shalal, “U.S. Skips Aegis Ashore Missile Test After Target Malfunction,” Reuters, June 26, 2015.) MDA’s table
similarly shows the test of December 7, 2006, as a test that did not result in the launch of an SM-3. MDA
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Navy Aegis Ballistic Missile Defense (BMD) Program

b. issued a news release on this test, which stated that an SM-3 was not launched “due to an incorrect system
setting aboard the Aegis-class cruiser USS Lake Erie prior to the launch of two interceptor missiles from the
ship. The incorrect configuration prevented the fire control system aboard the ship from launching the first
of the two [SM-3] interceptor missiles. Since a primary test objective was a near-simultaneous launch of two
missiles against two different targets, the second interceptor missile was intentionally not launched.” MDA
counts the test of December 7, 2006, as an unsuccessful intercept in its count of 31 successful intercepts in
37 launches through July 29, 2015.
c. MDA’s table shows this as a test that did not result in the launch of an SM-3. MDA as of November 10,
2015, had not issued a news release discussing this event. MDA’s count of 32 successful intercepts in 39
launches through November 1, 2015, does not appear to include this test, suggesting that this was
considered a “no test” event—a test in which there was a failure that was not related to the Aegis BMD
system or the SM-3 interceptor.


Author Information

Ronald O'Rourke

Specialist in Naval Affairs



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Congressional Research Service
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