On Friday night, April 11, 2025, President Donald Trump made a big call, signing a memo that hands the U.S. military control over a stretch of federal land along the southern border. It’s a narrow strip called the Roosevelt Reservation, running through California, Arizona, and New Mexico—a 60-foot-wide buffer set aside back in 1907 for border security. Trump’s order lets troops patrol this land, detain anyone crossing illegally, and even build more of his signature border wall.
This isn’t Trump’s first time leaning on the military for border control. During his first term, he sent troops to the same area to help put up barriers and slow down migrant crossings. But this move feels different—bigger. The memo, which went out to the heads of Defense, Homeland Security, Interior, and Agriculture, says the military needs to take a “more direct role” because the border’s “under attack” from all sorts of threats. Trump’s framing it as a crisis, pointing to drugs, crime, and illegal immigration as reasons to act fast. He’s calling it a “military mission to seal the border,” which has a ring of urgency that’s hard to miss.
Here’s what’s happening on the ground: the military can now treat parts of the Roosevelt Reservation like a base. If someone crosses there, they’re technically trespassing on military property, not just sneaking into the U.S. Troops can hold them until Border Patrol shows up to handle arrests or deportations. It’s a workaround for a law called the Posse Comitatus Act, which keeps the military from acting like cops on U.S. soil. By turning the land into a “military installation,” Trump’s team thinks they’ve found a legal loophole. But not everyone’s convinced—some experts are raising red flags, saying it could still break that 1878 law.
The plan’s starting small, with a “phased” rollout on a limited chunk of land. Defense Secretary Pete Hegseth gets to pick where, and after 45 days, he’ll decide if it’s working or if they need to expand. The memo also greenlights building walls and setting up surveillance gear, like cameras and sensors, to keep an eye on things. Native American reservations are off-limits, which is one line Trump’s not crossing here.
Trump’s been hammering border security since day one of his second term. Right after his inauguration, he declared a national emergency at the border, sending thousands of troops to back up Border Patrol. He’s promised a massive deportation push, and this move fits that vibe—tough, in-your-face, and all about control.
Interestingly, illegal crossings have actually dropped lately, with March 2025 seeing just 7,200 migrant encounters compared to over 189,000 a year ago. Some say that’s thanks to Trump’s policies; others point to Mexico cracking down on its side.
Aaron Reichlin-Melnick from the American Immigration Council are calling it a risky dodge around military limits, warning it could lead to legal fights. Environmental groups are upset, too, saying tanks and walls will wreck fragile desert ecosystems. On the flip side, Trump’s supporters see it as a long-overdue stand to protect the country, arguing the border’s been too porous for too long.
By April 20, the Defense and Homeland Security departments have to report back to Trump with ideas on whether to use the Insurrection Act—an old law from 1807—for even more aggressive moves, like mass deportations. That’s got some folks nervous about where this is headed.