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April 25, 2024
The Terminal High Altitude Area Defense (THAAD) System
Background
Figure 1.THAAD Fire Unit
According to the Department of Defense (DOD), the
Terminal High Altitude Area Defense (THAAD) system
(Figure 1) is a key element of U.S. ballistic missile defense
(BMD). THAAD employs interceptor missiles, using “hit-
to-kill” technology, to destroy threat missiles. Reportedly,
THAAD is capable of engaging targets at ranges of 150–
200 kilometers (km). THAAD covers the BMD middle tier
and defends a larger area than the Patriot Air and Missile
Defense System. It complements the Patriot, the Navy’s
AEGIS Missile Defense System, and the Ground-based
Midcourse Defense System.
A THAAD battery consists of 95 soldiers, six truck
mounted launchers, 48 interceptors (eight per launcher),
Source: U.S. Indo-Pacific Command News, https://www.pacom.mil/
one Army/Navy Transportable Radar Surveillance and
Media/News/Article/707735/missile-system-would-greatly-increase-
Control Mode 2 (AN/TPY-2) radar, and a Tactical Fire
defense-capability-in-south-korea/, accessed April 16, 2024.
Control/Communications component. THAAD provides
Combatant Commanders a rapidly deployable capability
Brief History of the THADD Program
against short-range (up to 1,000 km), medium-range
According to the Center for Strategic and International
(1,000–3,000 km), and limited intermediate-range (3,000–
Studies (CSIS) Missile Defense Project, the Army began
5,000 km) ballistic missile threats inside or outside the
developing THAAD in 1992. In December 1995, the Army
atmosphere during their final (terminal) phase of flight.
attempted its first THAAD intercept test, which was
THAAD was developed by Lockheed Martin Corporation,
unsuccessful. Five successive test flights—taking place
headquartered in Bethesda, MD. Lockheed Martin is
from 1996 to 1999—also failed. The Army redesigned
manufacturing THAAD in Troy, AL. The Missile Defense
THAAD and relaxed requirements for intercepting targets
Agency (MDA) is responsible for the development of
at lower altitudes. Between 2006 and 2019, the Army and
THAAD. According to the MDA,
the MDA conducted 18 THAAD intercept tests. Fourteen of
the tests were successful, and four were cancelled prior to
MDA is responsible for the sustainment of the
launch due to target malfunctions.
THAAD missile defense unique and development
items, while the U.S. Army is responsible for the
Current THAAD Program Activities
operations and sustainment of the common items.
The FY2021 National Defense Authorization Act (NDAA)
MDA funding provides sustainment for all fielded
(P.L. 116-283) authorized and funded the procurement of
THAAD batteries, ensures THAAD assets are
an eighth THAAD battery. On April 21, 2022, Lockheed
properly maintained and crews are trained to meet
Martin received a contract totaling $74 million to produce
Combatant Commanders’ needs.
this THAAD battery for the MDA, expected to be fielded
by 2025. According to the MDA, as of January 2024, this
The Army provides soldiers for THAAD units. As such, the
THAAD battery was still in production. As of October 1,
ability to field and operate THAAD batteries can be
2023, the MDA had delivered 799 operational THAAD
affected by recruiting and retention shortages, as well as the
interceptors to the U.S. Army and Foreign Military Sales
availability of qualified critical technical military
(FMS) customers.
occupational specialties.
THAAD Overseas Deployments
The Army currently has seven THAAD batteries. The first
THAAD has been deployed on a number of occasions in
THAAD battery (A Battery, 4th Air Defense Artillery
response to potential ballistic missile threats. According to
Regiment, 11th Air Defense Artillery Brigade) was activated
an April 2013 Federal Register notice,
in May 2008 at Ft. Bliss, TX, and the seventh THAAD
battery was activated in December 2016. According to
The U.S. Secretary of Defense directed the Army to
2019’s Army Air and Missile Defense 2028, three THAAD
deploy a THAAD battery immediately to Guam on
batteries are based at Ft. Bliss, two batteries are based at Ft.
an emergency basis in response to potential North
Cavazos, TX, and one battery is based in South Korea and
Korean missile launch activity. Since the temporary
one in Guam.
deployment of the THAAD battery in 2013, DOD
validated the enduring requirement for a THAAD
battery in Guam to ensure continued defense of the
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The Terminal High Altitude Area Defense (THAAD) System
homeland against existing and emerging missile
first operational intercept in a combat environment by
threats by potentially hostile states in the region.
any nation.
Stars and Stripes reported in May 2022 that the Army
• Saudi Arabia has signed multiple FMS cases for
would relocate the THAAD battery on Guam from
delivery of seven THAAD batteries and supporting
Andersen Air Force Base, Guam, to the nearby Marine
equipment.
Corps base, Camp Blaz, Guam, which is currently under
construction.
Potential Congressional Oversight
Considerations
South Korea
On July 7, 2016, the U.S. and South Korean governments
Adequacy of Current THAAD Force Structure
decided to deploy a THAAD battery to U.S. Forces Korea
The Army has said it plans to have eight Active Component
as a defensive measure designed to ensure the security of
THAAD batteries fielded by 2025. Two of these batteries
South Korea and to protect alliance military forces from
are seemingly committed on a long-term basis to Guam and
North Korea’s use of weapons of mass destruction and
South Korea, leaving six batteries available for contingency
conventional ballistic missile threats. The THAAD battery
operations. Of these six batteries, at least one or more
is stationed at a South Korean military base in Seongju,
batteries are unlikely to be available for contingency
about 130 miles south of Seoul.
operations due to scheduled upgrades or maintenance.
Europe and the Middle East
Also affecting THAAD forces is the reported stress on
THADD has also been deployed outside the Indo-Pacific
Army air and missile defense units, described as “among
region. According to CSIS,
the most overworked [units] in the US military, manning
In April 2019, the United States temporarily
missile systems across the globe to provide around-the-
deployed THAAD to Deveselu, Romania while its
clock deterrence against adversaries including North Korea,
Aegis Ashore system received maintenance.
China, Iran and Russia,” with one Army official noting in
Following drone and missile attacks on Saudi oil
2023, “it’s simple, pure math. We have more missions than
we have air defense capability.” One possible means to
facilities, the United States deployed a THAAD
reduce stress on existing THAAD units and meet
battery to Saudi Arabia in October 2019. This
potentially growing mission requirements could be to create
system was withdrawn in mid-2021.
more THAAD units. In this regard, Congress might decide
2023 Middle East Deployment
to examine the adequacy of the Army’s THAAD force
structure and assess whether it would be practical to create
On October 21, 2023, the Secretary of Defense directed the
THAAD units in the Army National Guard.
deployment of a THAAD battery, as well as additional
Patriot battalions, to locations throughout the region to
Transferring THAAD from the MDA to the Army
increase force protection for U.S. forces, bolster regional
Talks of transferring THAAD from MDA to the Army have
deterrence efforts, and assist in the defense of Israel.
been ongoing for about a decade. Reportedly, MDA and
FY2025 THAAD Budget Request
Army leadership suggested if Congress were to authorize a
transfer, they would not oppose the transfer provided
For FY2025, the MDA requested
necessary funding is made available and not taken from
$732 million to continue the development of
other programs within the service. There is a precedent for
THAAD system builds to increase interceptor
such a transfer, as MDA developed the Patriot Air and
capability and weapon system performance to
Missile Defense System and later transferred it to the Army.
address the current and evolving threat, to include
significant improvements which will provide the
The Government Accountability Office (GAO) noted that
capability to counter more advanced threats;
the FY2018 National Defense Authorization Act (NDAA)
procure 12 THAAD interceptors; and begin initial
(P.L. 115-91) required the Secretary of Defense to transfer
engineering efforts supporting integration of the
the acquisition authority of all missile defense programs
that had received full-rate production authority (including
THAAD weapon system into the Army Integrated
THAAD) to the services responsible for their operation.
Air and Missile Defense Battle Command System
The Army opposed the transfer of THAAD at the time
(IBCS) architecture.
because it could not meet its global mission requirements.
THAAD Foreign Military Sales (FMS)
According to GAO, at that point, Congress, MDA, and the
Other nations have acquired or intend to acquire the
Army were at an impasse. Because the Army seemingly is
THAAD system. According to the MDA, as of January
meeting THAAD’s global mission requirements, Congress
2024:
might reexamine the potential benefits and drawbacks of
transferring THAAD to the Army.
• Two THAAD batteries had been delivered to the United
Arab Emirates and are fully operational. The UAE’s
Andrew Feickert, Specialist in Military Ground Forces
THAAD successfully intercepted Houthi militant
ballistic missiles in January 2022, marking THAAD’s
IF12645
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The Terminal High Altitude Area Defense (THAAD) System
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