On April 11, 2025, President Trump announced a “military mission for sealing the southern border of the United States and repelling invasions.” The plan includes “use and jurisdiction by the Department of Defense” over designated federal lands along the southern border, border-barrier construction and placing of detection and monitoring equipment, and enabling of military activities on the designated “military installation.” It includes transferring authority to the Department of Defense over the Roosevelt Reservation, a portion of federal land along the border that is 60 feet wide.
The memorandum states that the plan will be implemented initially on a “limited sector” of federal lands designated by the Secretary of Defense, and may be extended by the Secretary of Defense at any time to additional federal lands along the southern border in coordination with other officials and “executive departments and agencies as appropriate.”