Pentagon to send up to 1,500 active duty troops to help secure U.S.-Mexico border, officials say

Dogs are near a border wall separating Mexico from the United States Wednesday, Jan. 22, 2025, in San Diego. (AP Photo/Gregory Bull)

WASHINGTON — The Pentagon will begin deploying as many as 1,500 active duty troops to help secure the southern border in the coming days, U.S. officials said Wednesday, putting in motion plans President Donald Trump laid out in executive orders shortly after he took office to crack down on immigration.

Acting Defence Secretary Robert Salesses was expected to sign the deployment orders on Wednesday, but it wasn’t yet clear which troops or units will go, and the total could fluctuate. It remains to be seen if they will end up doing law enforcement, which would put American troops in a dramatically different role for the first time in decades.

The officials spoke on condition of anonymity because the announcement has not yet been made.

The active duty forces would join the roughly 2,500 U.S. National Guard and Reserve forces already there. There are currently no active duty troops working along the border.

The troops are expected to be used to support border patrol agents, with logistics, transportation and construction of barriers. They have done similar duties in the past, when both Trump and former president Joe Biden sent active duty troops to the border.

Troops are prohibited by law from doing law enforcement duties under the Posse Comitatus Act, but that may change. Trump has directed through executive order that the incoming secretary of defence and incoming homeland security chief report back within 90 days if they think an 1807 law called the Insurrection Act should be invoked. That would allow those troops to be used in civilian law enforcement on U.S. soil.

The last time the act was invoked was in 1992 during rioting in Los Angeles in protest of the acquittal of four police officers charged with beating Rodney King.

The widely expected deployment, coming in Trump’s first week in office, was an early step in his long-touted plan to expand the use of the military along the border. In one of his first orders on Monday, Trump directed the defence secretary to come up with a plan to “seal the borders” and repel “unlawful mass migration.”

On Tuesday, just as Trump fired the Coast Guard commandant, Adm. Linda Fagan, the service announced it was surging more cutter ships, aircraft and personnel to the “Gulf of America” -- a nod to the president’s directive to rename the Gulf of Mexico.

Trump said during his inaugural address on Monday that “I will declare a national emergency at our southern border. All illegal entry will immediately be halted, and we will begin the process of returning millions and millions of criminal aliens back to the places in which they came.”

Military personnel have been sent to the border almost continuously since the 1990s to help address migration. drug trafficking and transnational crime.

In executive orders signed Monday, Trump suggested the military would help the Department of Homeland Security with “detention space, transportation (including aircraft), and other logistics services.”

In his first term, Trump ordered active duty troops to the border in response to a caravan of migrants slowly making its way through Mexico toward the United States in 2018. More than 7,000 active duty troops were sent to Texas, Arizona and California, including military police, an assault helicopter battalion, various communications, medical and headquarters units, combat engineers, planners and public affairs units.

At the time, the Pentagon was adamant that active duty troops would not do law enforcement. So they spent much of their time transporting border patrol agents to and along the border, helping them erect additional vehicle barriers and fencing along the border, assisting them with communications and providing some security for border agent camps.

The military also provided border patrol agents with medical care, pre-packaged meals and temporary housing.

It’s also not yet clear if the Trump administration will order the military to use bases to house detained migrants.

Bases previously have been used for that purpose, and after the 2021 fall of Kabul to the Taliban, they were used to host thousands of Afghan evacuees. The facilities struggled to support the influx.

In 2018, then-defence secretary Jim Mattis ordered Goodfellow Air Force Base in San Angelo, Texas, to prepare to house as many as 20,000 unaccompanied migrant children, but the additional space ultimately wasn’t needed and Goodfellow was determined not to have the infrastructure necessary to support the surge.

In March 2021, the Biden administration greenlighted using property at Fort Bliss, Texas, for a detention facility to provide beds for up to 10,000 unaccompanied migrant children as border crossings increased from Mexico.

The facility, operated by DHS, was quickly overrun, with far too few case managers for the thousands of children that arrived, exposure to extreme weather and dust and unsanitary conditions, a 2022 inspector general report found.

Lolita C. Baldor and Tara Copp, The Associated Press