The Pentagon’s effort to establish a comprehensive missile defense system on Guam is at risk of falling behind schedule due to unresolved planning and organizational issues, according to a new report by the Government Accountability Office (GAO).
The 42-page report, titled “Missile Defense: DOD Faces Support Challenges for Defense of Guam,” details the Defense Department’s progress and persistent challenges in developing the Guam Defense System (GDS), which is intended to safeguard the island and its military installations against missile threats amid rising military activity by China.
GDS, a planned $8 billion missile shield, will provide 360-degree protection against ballistic, cruise, and hypersonic threats on Guam—a strategic U.S. territory in the Indo-Pacific. Deployment will roll out in phases across 16 sites from 2027 to 2032, according to the GAO report.
As of March 2025, Guam’s existing missile defense system included components of the Terminal High Altitude Area Defense (THAAD) system. The setup comprised six mobile missile launchers and one radar.
GAO warned that the Defense Department faces potential delays in deploying the GDS due to the absence of a clear strategy for transferring control from the Missile Defense Agency (MDA) to the military services.
GAO said the Pentagon has also not defined staffing requirements or a timeline for sending service members to Guam to operate and maintain the system.
“Without establishing a strategy that includes a timeline and plan for the transfer of operation and sustainment responsibilities, the military services and MDA face preparedness and funding challenges,” the GAO said.
The report recommends that the Defense Department create a detailed plan for transferring responsibilities to the military services, clarify the Army’s future role on Guam, and finalize personnel and infrastructure requirements needed to sustain operations.
