President Donald Trump may be on the verge of opening a whole new front in America’s war on terror that would hit much closer to home: Mexico.

In a Tuesday interview with conservative radio host Bill O’Reilly, Trump said his administration will soon give Mexican drug cartels the same distinction as al-Qaeda, ISIS, and Boko Haram: designating them as “foreign terrorist organizations.”

That label would make it illegal for anyone in the US to knowingly provide support to the drug cartels. It would also allow the US government to sanction anyone who funds them, deport their members from America, and bar any affiliate from entering the US.

“I will be designating the cartels,” the president told O’Reilly. “We are losing 100,000 people a year to what is happening and what is coming through from Mexico,” he continued without citing where he got that statistic, adding, “they have unlimited money, the people, the cartels, because they have a lot of money, because it is drug money and human trafficking money.”

It’s therefore that possible Trump’s move could see US drug dealers labeled and treated as terrorist supporters. What most worries critics about Trump’s comments, though, is that the designation opens up the possibility that Trump could authorize US military force against the cartels without Mexico’s permission.

“It’s a terrible idea in part because it will reduce Mexican cooperation as many in Mexico fear it’s a first step toward some kind of military intervention, which Trump keeps mentioning when he talks to Mexican presidents,” Roberta Jacobson, the US ambassador to Mexico from June 2016 to May 2018, told me.

Trump is obsessed with fighting drug cartels

Trump has long focused on Mexico, making his plan to build a border wall to keep drug smugglers and undocumented immigrants out of the US a pillar of his presidency.

But his renewed focus on the cartels came after six children and three mothers — all Mormon US-Mexico dual citizens — were killed by gunmen on November 5. That same day, Trump tweeted it was “time for Mexico, with the help of the United States, to wage WAR on the drug cartels and wipe them off the face of the earth.”

This is the time for Mexico, with the help of the United States, to wage WAR on the drug cartels and wipe them off the face of the earth. We merely await a call from your great new president! — Donald J. Trump (@realDonaldTrump) November 5, 2019

The problem, though, is that Mexico’s government strongly opposes any unauthorized American military intervention.

“There is no political will in Mexico to invite US troops in. It is both an issue of nationalistic pride and an understanding in Mexico that what fuels drug cartels are weapons sold to them in the United States and drugs consumed by Americans,” Jana Nelson, a Mexico expert at the Wilson Center think tank in Washington, DC, told me. “From the Mexican perspective, the root cause of violence is on the other side of the border.”

“Cutting the cartel’s access to military-grade weapons, bought in the United States and smuggled into Mexico, is an effective way to limit the their firepower,” Nelson continued. “Intelligence coordination between the Mexican and the American government for operations against the cartels is also effective, especially when using the Mexican Navy for operations, which is less likely to tip off drug cartels.”

Mexico’s Foreign Ministry confirmed Nelson’s thinking in a Tuesday night statement after Trump’s comments to O’Reilly. “The Government of Mexico will continue its diplomatic work towards an understanding that, through cooperation and intelligence, guarantees the security of both countries,” the statement said, also noting it will “seek a high-level meeting as soon as possible to present Mexico’s position and hear the views of the US authorities.”

Indeed, experts in Mexico aren’t sure that Trump’s plan will really change the situation. It’s “not obvious it’ll have any impact on violence in Mexico and much less on drug flows,” Luis Rubio, the president of the Mexican Council on Foreign Relations, told me. “If the US mishandles it, it could provoke a middle-class run, which is the reason the US government has always been careful with such initiatives.”

Trump’s comments, then, have clearly increased tensions between the two neighbors by touching on a very sensitive subject in Mexico — one that could lead to a fight over whether the US may soon engage in another war.

Why Mexico balks at having US troops invade to fight drug cartels

This is a tough moment for Mexico’s leftist President Andrés Manuel López Obrador —commonly known as AMLO — who so far has maintained a good working relationship with Trump despite trade and immigration disputes. But Trump’s desire to name Mexican drug cartels as terrorists might open a rift between the two leaders, experts say.

“In the unlikely event that Obrador invited US troops in, it would be his political undoing,” Nelson, who focused on Mexico in the private sector, told me. “The Mexican public would push back on him.”

AMLO still faces pressure to do something about the drug cartel problem in his nation. Last month, Mexican authorities severely botched an operation to arrest notorious Sinaloa drug cartel leader El Chapo’s son, Ovidio Guzmán López. Video released by the government showed security personnel arresting him in Culiacán on October 17, only to let him go after cartel members were shot and wounded in an ambush as part of a peace offering.

It was a massive embarrassment for AMLO, who came to power promising to solve the scourge of violence with “hugs, not bullets.” He’s failed on that front, according to the Mexican government’s own numbers. There were 14,603 murders from January to June, compared to the 13,985 homicides tallied during the same period last year. That means Mexico could surpass the 29,111 total murders from 2018, which was an all-time high.

The situation is so bad that even 2020 Democrats have spoken openly about sending US troops to Mexico. “There is a scenario where we could have security cooperation,” South Bend, IN, Mayor Pete Buttigieg told a Latino forum in Los Angeles two weeks ago. But he added a major caveat, “I’d only order American troops into conflict if American lives were on the line and if it was necessary to meet treaty obligations.”

Nelson says that AMLO’s administration already works with the US intelligence community and the State Department’s drug and law enforcement officials on curbing drug cartel violence. But his team hasn’t cooperated as closely with America mainly because AMLO fired scores of government employees he believes aren’t ably serving the public, leaving major gaps in the country’s ability to fight the cartels.

This means AMLO is trying to balance not getting too much US help with relying on a skeleton crew in his own government. Still, he’s the leader, and having Trump send troops would be an admission that he’s not up to the task and is permitting violations of Mexico’s sovereignty.

“Mexico will never accept any action that violates our national sovereignty,” Marcelo Ebrard, Mexico’s foreign minister, tweeted Tuesday night.

If Trump does designate Mexican drug cartels as terrorists, then, you can expect US-Mexican relations to take a turn for the worse.