DOD says troop deployments and Guantanamo housing have helped seal southern border; civilian agencies remain lead

Chairman Mike Rogers convened the House Armed Services Committee to begin fiscal 2026 posture hearings and pressed Department of Defense witnesses on the department's role at the southern border.

Rafael Leonardo, performing the duties of Assistant Secretary of Defense for Homeland Defense and Hemispheric Affairs, told the committee the DOD has supported Department of Homeland Security efforts to "seal our border" and reported that the department’s accounting so far for its support is $376,000,000. He said the department has deployed roughly 6,700 Title 10 active‑duty personnel to the border and has ordered as many as 10,000 in place or en route.

The hearing clarified roles and legal limits. Leonardo and General Greg Guillot, commander of U.S. Northern Command and NORAD, emphasized that DHS remains the lead federal agency and that DOD forces perform detection, monitoring and support missions rather than law enforcement. Guillot said Title 10 forces do not make arrests, do not transport migrants and "vector in the border patrol or a proper law enforcement agency to actually make the apprehensions." Robert Salasas, senior adviser to the deputy secretary of defense, told the panel that Immigration and Customs Enforcement (ICE) currently has housing capacity for about 45,000 higher‑threat detainees and that DOD is filling capacity shortfalls where requested by DHS.

Committee members pressed witnesses about Guantanamo Bay. Leonardo and Salasas said DOD has used Naval Station Guantanamo Bay to support DHS housing requests for select individuals who DHS determines should go there, and they described current operations as tailored and limited. Admiral Alvin Halsey, commander of U.S. Southern Command, told the panel his command is providing logistics and other support to maritime and partner operations in the region; when asked about a scenario housing 30,000 migrants at Guantanamo Bay, Halsey said planning estimates would require roughly 9,000 service members to support that scale but that the command had not been directed to expand to that level.

Members sought legal assurances. Representative Sara Jacobs asked explicitly whether Title 10 forces will detain migrants; Guillot replied, "I have no orders to conduct any detention," and added that units receive training on use‑of‑force standards and legal constraints, including posse comitatus considerations. The witnesses told committee members DOD has requested targeted authorities to counter unmanned aerial systems when those drones are conducting surveillance of deployed forces or installations.

The record the witnesses provided to the committee shows: approximately $376 million expended so far in DOD support, roughly 6,700 active‑duty personnel at the border with up to 10,000 ordered, that DOD performs detection and monitoring in support of DHS, and that DOD does not perform arrests or sustained detention absent DHS authority.

Looking ahead, Leonardo told members the department will continue to assess how long operations must remain in place and to coordinate costs and force requirements with DHS and the services. Guillot and Salasas said maintaining the mission at steady state will depend on DHS capacity, interagency planning and congressional resourcing.

The committee hearing left unresolved several implementation details lawmakers pressed on: how long specific units will remain deployed, the full lifecycle cost if housing requirements grow, and whether expanded authorities requested for counter‑UAS missions will be approved.

Ending note: witnesses thanked the committee for support and said DOD will continue to cooperate with DHS and Congress on force posture, authorities and the shift from surge to steady‑state operations.