Violence erupted across Mexico Sunday after the death of Jalisco New Generation Cartel (CJNG) boss “El Mencho,” known to authorities as Nemesio Rubén Oseguera Cervantes. The U.S. Embassy to Mexico advised American citizens in multiple states to shelter in place and only lifted that warning on Tuesday, when public transportation and businesses “return[ed] to normal operations.” The incident illustrates the problem with letting criminal enterprises run amok in the country and the difficulty of prying them loose.

“For years, large swaths of territory in our region, including large parts of Mexico … have been controlled by murderous drug cartels,” said President Donald Trump in his Tuesday night State of the Union address before Congress. He said his administration is “restoring American security and dominance in the Western Hemisphere, acting to secure our national interests and defend our country from violence, drugs, terrorism, and foreign interference.”

The CJNG is one of the most aggressive drug cartels, expanding to nearly 40 countries and all 50 U.S. states since its formation in 2009. The heavily armed cartel has attacked military forces with helicopters, grenades, drones, and mines. It is also one of the main cocaine suppliers to the U.S. market.

Two years ago, the U.S. offered a $15 million reward for information on El Mencho, who was added to the list of Most Wanted fugitives in 2016. The Mexican federal government had also offered a reward of 30 million pesos, or about $2 million. In February 2025, President Trump identified CJNG as a foreign terrorist organization.

For better or worse, the second Trump administration has taken an “all of the above” approach to countering drug traffickers, from closing the southern border, to aggressive immigration enforcement, to military strikes on drug boats in the Caribbean. So, it should come as no surprise that U.S. intelligence agencies “compiled a detailed target package for El Mencho,” as an anonymous official told Reuters, which Mexican authorities used for their operation. Mexico’s Ministry of Defense confirmed that the U.S. provided “complementary information” for the strike.

On Sunday, Mexico launched an operation to capture El Mencho at his compound at Tapalpa in the mountains of Mexico’s western Jalisco state. The raid turned into a shootout, in which government forces suffered three wounded (and reportedly one dead). However, they killed four people, injured El Mencho and two others who all died later, and arrested two others, besides capturing armored vehicles, rocket launchers, and other weapons.

Within hours, violence erupted across Mexico as cartel members set up checkpoints, seized vehicles, and burned them to choke roads. They looted gas stations and banks and swarmed the streets in Puerto Vallarta, a resort town on Jalisco’s Pacific Coast. Cartel members established a total of 252 roadblocks, including 85 in Jalisco. The unrest spread throughout 20 Mexican states, as far away as Quintana Roo, Mexico’s easternmost state, where Cancun and Cozumel are located. One estimate put the death toll as high as 70, including 25 members of the National Guard, a prison guard, and a state prosecutor on the government side, and at least 30 cartel members on the criminal side.

In addition to fighting government forces, various cartels or cartel factions may have been vying for power and control after El Mencho’s death, one security expert suggested. “When a drug cartel leader like El Mencho is taken off the board, there is a vacuum of power,” said Rep. Nathaniel Moran (R-Texas) on “Washington Watch,” “and you’re seeing more of these other second- and third-level individuals and groups trying to figure out who’s going to assume authority.”

In response, the Mexican government mobilized an additional 2,000 troops to Jalisco on Monday. A dozen states canceled school Monday, and more than 240 flights were canceled from Mexican airports, especially in Puerto Vallarta and Jalisco. Meanwhile, the American embassy directed U.S. government “in Guadalajara (Jalisco), Puerto Vallarta (Jalisco/Nayarit), Ciudad Guzman (Jalisco), Cancun (Quintana Roo), Playa del Carmen (Quintana Roo), Cozumel (Quintana Roo), Reynosa (Tamaulipas state), Tijuana (Baja California), and Michoacan” to “shelter in place and work remotely” and advised U.S. citizens to do the same.

Through at least seven updates on the security situation, the embassy gradually loosened the restrictions, saying on Monday that “the situation has returned to normal” in Quintana Roo, Sinaloa, and Tamaulipas. By Update Six (Tuesday), the situation was mostly back to normal, although U.S. government staff in Jalisco, Tijuana, and Monterrey still faced an embassy-imposed nighttime curfew and were warned to stay in metropolitan areas. Later Tuesday, Tijuana and Monterrey were also cleared.

Latin American cartels are particularly powerful right now due in part to the lax enforcement of previous administrations. In the U.S., the Biden administration allowed cartel members to enter the country with little hassle through its infamous refusal to guard the southern border. In Mexico, former President Andrés Manuel López Obrador (in office from 2018-2024) pursued a policy of “hugs, not bullets.” Naturally, organized criminal cartels took advantage of these soft-hearted policies to enrich and entrench themselves.

There are obvious downsides to taking out crime bosses, as Sunday’s violence showed. The military power of cartels and the havoc they can wreak is one reason why Mexican officials have not dismantled them before now. (Other reasons include the cartels corrupting, intimidating, or assassinating government officials.) But this violence also shows why the cartels must be confronted — for the good of Mexico, not to mention the United States.

Under new management, the governments of the United States and Mexico are working together to undo the cartels. Mexico has extradited a large number of cartel prisoners to the United States, where it is much harder to manage operations from prison. In August 2025, Mexico extradited CJNG’s alleged financial mastermind, Abigael González, to the United States amid a mass extradition. In September, the U.S. Drug Enforcement Administration (DEA) arrested 670 CJNG members in a single week.

At first glance, the partnership between Trump and the left-wing government of Mexican President Claudia Sheinbaum may seem unlikely. Perhaps corralling cartel kingpins is not Sheinbaum’s first choice of policy. But she seems to have calculated, based upon Mexico’s close economic relationship with the United States and the fate of other confrontational powers in the hemisphere (Venezuela and Cuba), that cooperation is the far superior option. What she doesn’t want is U.S. troops operating on Mexican soil or U.S. tariffs operating on the Mexican border. If American authorities provide intelligence and take custody of the worst offenders, so much the better.

From the Trump administration’s perspective, the goal was always to get Mexico to step up its own enforcement operations against cartels. Providing intelligence appears to be one way to achieve that. And keeping American forces out of harm’s way preserves them for many other tasks. “We want to see the government of Mexico and President Sheinbaum [making] progress in this area. We want to see them take full control,” said Moran. “We want to see these heads of these drug cartels come to justice. … We also want to see, on the back side of that vacuum of power, security in those regions handled by the appropriate authorities.”

El Mencho’s elimination was a joint triumph for the U.S. and Mexico, but it was only an early step towards scraping long-entrenched cartels out of the Mexican countryside. At the end of the day, however, the operation showed that even left-wing executives know how to capture criminals when they put their minds to it. The only conclusion is that many left-wing executives in the United States simply cannot be bothered to do so.