Soldiers are trained for combat. They exist to defend a state against aggression, or to keep order in extreme emergencies. Soldiers are not trained to be police, who are civilians charged with protecting and serving the population with minimal violence. They are not trained to be teachers, judges, or tax collectors. And soldiers are absolutely not trained to be migration agents.
Migrants are not “invaders,” as the Trump administration’s executive orders claim. They don’t have leaders, organization, or even common goals and reasons for fleeing, though most have humanitarian needs. Of those who have come to the U.S.-Mexico border since 2024, more than 40 percent are children, or parents with children. This is not a population demanding a response from combat-trained soldiers: not in the United States or anywhere else.
When governments make soldiers perform internal security missions involving long-term, non-emergency, open-ended interaction with civilians, especially vulnerable and trauma-affected civilians like migrants, the probability of human rights abuses skyrockets.
Long-term missions seeking to curb highly profitable illicit transactions—like cross-border drug or migrant smuggling—carry a high probability of corruption. This poses a threat to the integrity and capacity of military institutions, which are often difficult to hold accountable in the first place.
Using extremely harsh measures to control migration is a very political mission. Treating migrants like an “invasion” is a very political choice. If militaries become accustomed to taking on a politicized mission like this one, what happens when a president calls on them to carry out other politicized missions, like confronting peaceful protesters or labor movements? The migration mission sets a dangerous precedent.
Mexico
Mexico had already been undergoing a historic reversal in civil-military relations, conferring a long list of internal roles on its armed forces; WOLA has called it a “militarized transformation.” Its government transferred soldiers into a new military federal police force, the National Guard, giving it full power to police the country while placing it, first de facto and then officially, under the command of the Defense Ministry. Since its creation, that new branch of Mexico’s armed forces has participated heavily in migration enforcement, alongside other branches of Mexico’s military.
While WOLA has not seen evidence of direct U.S. training and equipping of Mexico’s National Guard, the Trump administration is aggressively supporting the Mexican government’s expansion of the military’s internal migration mission, as was also the case during Trump’s first term. In order to stave off a threat to impose tariffs at the beginning of February, President Claudia Sheinbaum agreed to deploy 10,000 additional National Guard personnel to Mexico’s northern border region, ostensibly to control migration and seize fentanyl.
The additional troops are now carrying out checkpoints, searches, roadblocks, and raids. In some areas, they are patrolling the quiet border jointly with U.S. Border Patrol in “mirrored” fashion. Soldiers are interacting with civilians, including migrants, more often than before.
Border Patrol and Mexican National Guard carry out “mirrored” patrol in Arizona. Source: Border Patrol Tucson Sector on Twitter.
This response further expands the military role in Mexico’s internal security, with all the risks that it entails for human rights, especially those of migrants, as well as corruption and civil-military relations.
The deployment, meanwhile, makes no strategic sense. It is difficult to interdict illicit synthetic drugs, which are very small in volume. The task badly vexes U.S. law enforcement inside the United States. To the extent that it is possible, these illicit substances are more likely to get interdicted at transit bottlenecks in Mexico’s interior than along a 2,000-mile-long border.
Migrants, meanwhile, must already run a gauntlet of patrols and checkpoints run by civilian and military forces and organized criminals as they cross Mexico, requiring most to pay smugglers and corrupt officials. There is no reason to expect that adding more National Guard personnel will make it harder for a smuggler to bring migrants to the border. Past experience indicates that it will just create an additional “cost of doing business” for smugglers.
By signaling that Mexico’s internal troop deployment appeased its demand for action to stave off tariffs, the Trump administration sent a strong message that this is the model of security and civil-military relations that the United States wants Latin American nations to follow in the 21st century. While the U.S. government has supported, and at times funded, the Mexican military’s role in counter-drug operations for decades, expanding this support to immigration enforcement is a major escalation of this model.
Guatemala
In Guatemala, too, the Trump administration is actively encouraging a big new military role in migration control. During Secretary of State Marco Rubio’s February 5 visit to the country, Guatemalan President Bernardo Arévalo announced that the U.S. government would be assisting the formation of new border task forces combining Guatemalan police and military personnel.
These will be charged with combating organized crime and interdicting drugs and smuggled migrants in Guatemala’s border regions. The first began operating along Guatemala’s border with El Salvador and Honduras on February 25.
This will expand the internal policing roles of a military with a serious history of human rights abuses, including what a Truth Commission reporting on Guatemala’s 1960-1996 armed conflict called genocide. Even in the gravest cases, accountability has been very difficult to achieve.
Guatemala’s Army meanwhile faces multiple allegations of involvement in corruption and drug trafficking, including some former officers’ confessions of assistance to criminal groups like Mexico’s Jalisco New Generation Cartel, which the Trump administration just added to the State Department’s list of foreign terrorist organizations.
Though much remains undone, Guatemala has taken important steps, especially during the past 15 years, to exert civilian control over the armed forces and to keep soldiers in the barracks by trimming internal security roles. Those steps built on the promise of the 1996 peace accord, which created a civilian police force and placed internal security more firmly under civilian control. This big new internal border role is a setback to this past progress.
It also appears likely to repeat the frustrating experience of the “Inter-Agency Task Forces” of the mid-2010s, military-police-prosecutor border units set up with U.S. support. These units ended up failing to operate effectively, misused U.S.-donated equipment against a UN-assisted anti-corruption body, and ultimately collapsed.
Texas
The United States, too, is seeing an expansion of internal military roles, with soldiers ever more involved in controlling migration at home. On February 15 and 19, U.S. Border Patrol deputized 590 Texas state National Guard personnel, essentially allowing them to enforce immigration law like Border Patrol agents. That means these National Guard personnel are now empowered to apprehend and, if necessary, to confront civilians whom they believe to be in the United States without authorization.
Border Patrol Chief Mike Banks (center, back to camera) deputizes National Guard personnel in south Texas. Source: Border Patrol Rio Grande Valley Sector on Twitter.
National Guard members are military personnel. They undergo the same training as do regular U.S. armed forces. If they are Army National Guard personnel, their uniforms bear “U.S. Army” tape.
Longstanding U.S. law—the Posse Comitatus Act of 1878—seeks to prevent exactly these kinds of long-term, open-ended internal missions involving regular contact and confrontation with civilians on U.S. soil. The risks of such missions for democratic civil-military relations are too great.
The National Guard mission at the border relies on one of the legal exceptions to the Posse Comitatus Act—the vaguely worded Sec. 502(f) of Title 32, U.S. Code—to use the National Guard in “support of operations or missions undertaken…at the request of the President or Secretary of Defense.”
There is no emergency to justify such a mission. In Border Patrol’s Rio Grande Valley Sector, where the first deputized soldiers are operating, 3,000 Border Patrol agents are apprehending just 50 migrants per day: a rate of 0.5 migrant apprehensions per agent per month.
WOLA and partners have already documented how frequently the Texas National Guard has been improperly using both lethal and non-lethal force against migrants, in many cases to deny them the legal right to seek asylum, and even denying water and first aid to families and children. WOLA called this aggressive use of soldiers on U.S. soil a “dangerous precedent” in 2024. This is a big step beyond.
If the Trump administration is permitted to declare an “invasion” to give soldiers a big open-ended role on U.S. soil at the border, we should fear the use of other emergency measures to use soldiers for other internal political purposes. This mission opens the possibility of big further distortions in the U.S. military’s role as we’ve known it.
Mass deportations
The use of military force against migrants goes beyond the National Guard. The Trump administration is calling on regular military forces as well. So far, 3,600 active-duty soldiers, marines, and Air Force personnel have been called to help guard a quiet border. That number is to increase soon to 9,000.
It’s so quiet that the border-wide number of troops is greater than the monthly number of apprehended migrants, estimated at 8,450 in February. Yet the troops deployed come “from some of the most experienced and highest readiness elite units in the Army,” noted Jennifer Kavanagh of Defense Priorities. The politicized push to rush troops to the border is idling personnel in whom the Defense Department has invested heavily.
Active-duty soldiers put up concertina wire near San Diego. Source: Border Patrol San Diego Sector on Twitter.
Military aircraft are carrying out deportation flights; the treatment of the migrants aboard, some of them families with children, has generated expressions of protest from nations including Brazil, Colombia, and India.
Military facilities, like Buckley Space Force Base in Colorado and Fort Bliss in El Paso, are being used as staging and transportation areas for the administration’s growing mass deportation campaign, and this is probably just the start. ICE does not have the personnel to carry out “mass deportation” on its own. We can expect to see more soldiers playing supporting roles in deporting people all over the U.S. interior. This may include active-duty military, through an invocation of the rarely used Insurrection Act of 1807.
Shackled migrants board a C-17 military aircraft being used to deport them. Source: CBP on Twitter.
More than 700 military personnel are expanding the Guantánamo Bay Naval Station to accommodate potentially as many as 30,000 migrants. The administration has still given no reason why it would take migrants—many with no criminal records at all, some of them asylum seekers—to an inaccessible base far from contact with attorneys or loved ones.
Using the military and the Guantánamo base exhibits a reckless disregard for costs at a time when the new administration is seeking to slash the federal government, including the Defense Department. Though it can only offer educated guesses because much data is classified, a Niskanen Center analysis estimated that Guantánamo detentions cost U.S. taxpayers well into the millions of dollars per inmate per year. “By comparison, the current cost of detention in ICE facilities on the U.S. mainland—estimated to accommodate approximately 41,000 individuals—is roughly $260 per migrant (adjusted for inflation) per day, or about $95,000 annually.”
Contributing to the logistics of mass deportation by running transportation and staging “camps” means playing non-combat roles with big human rights implications. Soldiers’ training offers little preparation for that. Potentially worse, involving the U.S. military in mass deportation is to involve our nation’s fighting force in a politicized internal mission.
The U.S. military—which prides itself on being apolitical—is being forced to lend itself to the current administration’s domestic political priorities. This threatens a historic break with more than a century of restraint in the United States’ democratic civil-military relations.
Conclusion
As the Trump administration expands and supports military roles in migration enforcement, both at home and throughout the Americas, some of its domestic efforts will run into judges who find these activities unconstitutional. But many efforts will not stop in the courts, especially those involving U.S. assistance and pressure on countries in Latin America.
These activities carry grave risks for human rights and democracy in both Latin America and in the United States. Expansion of military roles, using the excuse of migration and the false argument of an “invasion,” needs to stop as soon as possible, before it expands or comes to be seen as normal.
In the region, it threatens to accelerate the reversal of a key element of the region’s transitions from dictatorship to democracy going back to the 1980s, which saw the armed forces return to the barracks while states created civilian public security ministries and professional police forces. Both in the hemisphere and at home, it also promises to dilute armed forces’ focus on their core mission: defending their nations from aggression. Turning militaries into an all-purpose domestic tool blunts both their readiness and their morale.
The work to prevent it, then, can’t just be up to judges and litigators. It demands greater vigilance from members of Congress, journalists, and all citizens who value the military’s role in democracy. We must raise our voices and not look away.
