US General Mark Milley, Chairman of the Joint Chiefs of Staff testifies during a House Armed Services Committee hearing on the defense budget request on Capitol Hill in Washington, D.C., on March 29, 2023.

US General Mark Milley, Chairman of the Joint Chiefs of Staff testifies during a House Armed Services Committee hearing on the defense budget request on Capitol Hill in Washington, D.C., on March 29, 2023. Photo by ANDREW CABALLERO-REYNOLDS/AFP via Getty Images

Milley: Don’t Send Uninvited US Troops to Mexico

The top U.S. general recommends military training and law enforcement to stem drug and migrant flows—not special operators and other forces.

Watch Kevin Baron's interview with Gen. Mark Milley, part of Defense One's State of Defense series, here.

The U.S. military should not lead American counter-drug efforts in Mexico, nor operate against cartels there without the express consent of the Mexican government, said Joint Chiefs Chairman Gen. Mark Milley.  

Republicans and conservative media pundits have seized on border security, often accusing the Biden administration of devoting insufficient attention and security forces to the issue. In recent Senate and House hearings about the president’s defense budget request, Milley and Defense Secretary Lloyd Austin faced multiple questions from Republicans asking about the possibility of U.S. military intervention or for some greater role for troops in stopping the inbound flow of drugs, including fentanyl, and people. 

President Donald Trump, the frontrunner for the 2024 GOP presidential nomination, has asked for “battle plans” to invade Mexico to “conduct specific military operations to destroy the cartels”, Rolling Stone reported this week. The article cited an internal Trump policy paper that says Mexico should be enlisted to help the U.S. with any counter-drug efforts, but says, “It is vital that Mexico not be led to believe that they have veto power to prevent the US from taking the actions necessary to secure its borders and people.”

On Friday, Milley responded. “I wouldn't recommend anything be done without Mexico’s support,” and with an express request from the Mexican government, the chairman said in an exclusive interview at the Pentagon with Defense One.

Milley, who has experience training Colombia’s forces, said he believes that training foreign military and local police is still the best option. 

“First of all, it's a whole-of-government, interagency approach, and law enforcement plays a very heavy role. The drug trafficking trade is fundamentally a law enforcement issue. It's a crime,” he said. “There are capabilities that we in the military have—intelligence, for example, or logistical support, or airlift, and those sorts of things. But also there’s capabilities and special operations forces that are—all these are possible, but these are very, very difficult policy decisions. And having spent a fair amount of time in Latin America, I would argue that the best thing that can be done is ‘by, with, and through’ the local governments that are friendly to the United States, and work with them and their militaries to try to stem the flow of drugs.”

“Look, it's a serious problem. It's a huge problem.” 

Several Republicans, including Rep. Morgan Luttrell, R-Tex., this week asked about or called for the Biden administration to designate Mexico’s cartels as terrorist organizations, rather than transnational criminal organizations. “That's the same thing, in my opinion,” Luttrell said in a House Armed Services Committee hearing on Wednesday.

Milley replied that most people entering the United States were “economic migrants…but not all of them. Some of them are not. Some of them are bad. They—who knows where they're coming from and what their intent is? So, that border crisis is very serious, and it's having a very negative effect on our society.” But he cautioned the committee against unilateral military action.

On Friday, he said the designation change would not come easy. 

“T​​hat'd be a legal policy choice,” Milley said. “Obviously, they're using terrorist tactics, and murdering people. They're conducting terrorist attacks in northern Mexico.”

But for U.S. military action to follow any such redesignation, he said, “We would have to go through a very rigorous decision-making process. And I would not recommend doing anything without the support and the approval of the Mexican government, because that would just lead to something worse than what you already have.” 

Milley is due to retire later this year when his four-year term as chairman expires. He served as senior military advisor to Trump from October 2019 through the end of the president’s single term in office in January 2021, and has been criticized for going beyond his advisory role in ways that may have subverted the commander-in-chief. 

On Thursday, Trump, who is running for re-election, was indicted by a Manhattan grand jury on more than 30 criminal counts for allegedly paying hush money to an adult entertainment actress with whom he allegedly had an affair. 

"You know, for me in uniform, as a general officer, chairman of the Joint Chiefs of Staff, or for anybody in uniform, it's entirely inappropriate for us to even comment on any ongoing legal action, so I'll refrain from any comment on that, thanks," said Milley.