On Saturday, during an interview at Univision’s Democratic presidential forum in Long Beach, Calif., I asked South Bend, Ind., Mayor Pete Buttigieg, one of only two military veterans in the Democratic field, to explain his foreign policy doctrine. Buttigieg, who has called for an end to America’s “endless wars,” told me he would commit U.S. troops to conflicts abroad only if there were no reasonable alternative in order to save American lives and protect the country’s alliances.

“All of those have to go together,” he explained, staking the kind of eloquent moderate view that has earned him praise among an increasing number of potential voters in Iowa and New Hampshire, where he is now leading in the polls and has begun to emerge as a viable alternative to vice president Joe Biden.

Buttigieg is a disciplined interviewee, rarely straying off his centrist message. But not always. On Saturday, I asked him whether he would favor officially designating certain Mexican drug cartels as “foreign terrorist organizations,” or FTOs, especially after the recent murder of nine American citizens, including six children, in Sonora, Mexico. Buttigieg did not hesitate. “I believe that should be on the table, because they’re spreading terror,” he said. A few hours later, Buttigieg doubled down, saying “there is a scenario” in which he would consider committing U.S. troops to Mexico as a matter of “last resort.”

This is far from a moderate position.

By opening the door to the potential designation of Mexican criminal organizations as terrorists, Buttigieg has aligned himself with a number of conservative voices in Congress and beyond.

In February, Republican Reps. Chip Roy (Tex.) and Mark Green (Tenn.) sent Secretary of State Mike Pompeo a letter urging the government “to consider designating many of the world’s most violent drug cartels” as FTOs. “These groups view America’s sovereign borders as merely minor inconveniences,” Roy and Green wrote, citing drug trafficking and human smuggling as growing threats.

President Trump soon endorsed the idea. A couple of weeks after the Pompeo letter, a group of editors at Breitbart asked Trump whether he was considering the move to label Mexican cartels as terrorist organizations. “We are,” Trump replied. “We’re thinking about doing it very seriously … Mexico, unfortunately, has lost control of the cartels.”

The move would greatly complicate an already strained bilateral agenda. If the Trump administration were to designate Mexican cartels as terrorist organizations, the U.S. government would be immediately granted a set of blunt diplomatic instruments that could have unforeseen consequences for both countries. The treasury secretary could seize or block all assets presumably related to the cartels. It would increase U.S. intelligence capabilities and the government’s ability to antagonize those under suspicion of abetting the cartels, including training, lodging, transportation, financial support and a long list of alleged activities. On those grounds, it would open the doors to a sudden increase in deportations.

Experts on Mexico’s drug war warn an FTO designation could weaken both countries’ efforts to combat cartel violence. Mexican diplomat Arturo Sarukhán, who was Mexico’s ambassador to the United States shortly after the country’s drug war began in 2006, has been critical of Buttigieg’s comments and the position of Republicans such as Trump, Green and Roy.

“It’s simplistic,” Sarukhán tweeted. “If your only tool is a hammer, then every problem looks like a nail.” According to Sarukhán, Mexican cartels are not interested in destroying the Mexican state, but would much rather establish a perverse “symbiosis.”

“The set of tools required to confront organized crime is far bigger than those used against terrorism,” Sarukhán concluded. Journalist Andrés Oppenheimer agrees. In a recent column, Oppenheimer warned the Trump administration not to open “a Pandora´s box by extending the definition of terrorism to groups that kill other people, whether by design or not.” Mexican cartels, Oppenheimer says, do not fit the definition of terrorism that the designation would require. For example, they lack a political agenda. “Mexican cartels are in it for the money, not to topple any government,” he writes.

I asked Roberto Velasco, a spokesman for Mexico’s Foreign Minister, whether the terrorist designation could have negative consequences in the fragile dynamic between both countries. He did not mince words: “A measure like the one candidate Buttigieg suggested would represent a direct intervention in Mexican affairs that, rather than advance binational cooperation in security matters, would have a counterproductive effect and lead to a confrontation,” he said.

Still, Republican voices seem undeterred. A couple of weeks ago, just days after the Mexican government’s controversial decision to release one of the sons of Joaquín “El Chapo” Guzmán following his capture in the city of Culiacán, Roy reiterated his position. In an op-ed for the Hill, Roy again called for the terrorist designation. “The United States can no longer sit idly while our friends in Mexico are being overrun,” he wrote. “Our backyard is on fire.”

After the brutal murders in Sonora, the calls to act more forcefully have understandably increased. “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,” Trump tweeted after news of the carnage.

Still, while the situation in Mexico is undeniably difficult, the designation of some of the country’s cartels as terrorist organizations seems disproportionate and counterproductive. It would be important to learn whether other Democratic candidates share Buttigieg’s openness for such an extraordinary measure.

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