Hegseth Approves Temporary Loan of Military “Heat Ray” to DHS for Border Testing

Defense Secretary Pete Hegseth signed a memo last month authorizing a temporary loan of one Active Denial System to the Department of Homeland Security for testing and potential development of tactics at the southern border, according to reporting on the document.

The memo authorizes the loan for seven months beginning in September. It states that the system “shall not be operated by DoW (Department of War) personnel” and places sole responsibility for employment, use, and development of tactics, techniques, and procedures with DHS. At the end of the period, DHS may request continued use.

The Active Denial System is a vehicle-mounted directed-energy weapon that emits millimeter waves, producing an intense heating sensation on the skin at ranges of roughly half a mile or more. Military descriptions characterize it as non-lethal, intended to create an intolerable sensation that prompts reflexive movement away from the beam. The system was previously considered for border use in earlier administrations and was deployed briefly in Afghanistan without operational combat use.

A Pentagon official’s social-media comment described the border as “a military installation and a battle lab for testing new systems, to include directed energy weapons.” DHS and CBP have indicated they evaluate technologies that can improve security while addressing operational needs. Legal and practical questions about use of force, effectiveness, and effects on individuals remain part of public discussion of the capability.

The loan keeps military personnel out of direct operation of the system on the border while giving DHS access to evaluate it.