❓WHAT HAPPENED: The Pentagon is expanding two new military zones at the southern border to further enhance border security.
👤WHO WAS INVOLVED: The Pentagon, U.S. Marine Corps, and U.S. Border Patrol.
📍WHEN & WHERE: The expansion was reported on June 25, 2025.
💬KEY QUOTE: “The establishment of a second National Defense Area increases our operational reach and effectiveness in denying illegal activity along the southern border,” said U.S. Northern Command chief General Gregory Guillot.
🎯IMPACT: The move further strengthens the border as illegal crossing numbers rapidly decline under President Donald J. Trump.
The Pentagon is designating two new military zones along the southwestern border in Arizona and Texas, intensifying the Trump administration’s efforts to further secure the southern border with Mexico, amid a sharp drop in migrant crossings.
The new zones, officially National Defense Areas, will be patrolled by U.S. troops. One will be added to the Marine Corps Air Station in Yuma, Arizona, and the other to Joint Base San Antonio in Texas. Officials say illegal immigrants entering these zones will be treated as trespassers and may be detained by troops until Border Patrol arrives.
“The establishment of a second National Defense Area increases our operational reach and effectiveness in denying illegal activity along the southern border,” said U.S. Northern Command chief General Gregory Guillot.
These additions bring the total to four newly established military zones along the border. Previously in April, a 200-mile, 60-foot-wide strip along New Mexico was added to a military base. A 63-mile zone near Fort Bliss, Texas, was also recently designated.
Nearly 9,000 active-duty troops are now deployed at the border. The buildup includes surveillance aircraft and U.S. Navy ships offshore, under Joint Task Force–Southern Border, led by U.S. Northern Command. Ground forces include combat-seasoned troops from the Army’s Fourth Infantry Division.
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