Mexico Increases Military Presence at U.S. Border to Combat Drug Trade

On the Mexican side of the border between Nogales, Sonora, and Nogales, Arizona, a dozen soldiers stand watch. Some vehicles heading north are stopped for inspection, while others are waved through. As the busiest crossing point between Sonora and Arizona, Nogales saw approximately 10.6 million crossings into the United States in 2024. But it is also a major corridor for fentanyl smuggling. Of the ten tonnes of fentanyl seized by U.S. Customs and Border Protection (CBP) in 2024, about 60% was confiscated at Nogales and other smaller Arizona-Sonora crossings. Luis Arturo Corrales Ley, the public safety commissioner in Nogales, Sonora, describes his state as a "springboard for drugs."

Mexico’s president, Claudia Sheinbaum, is determined to dismantle that springboard. Her strategy involves intercepting more fentanyl on the Mexican side of the border, thereby reducing the quantities detected by U.S. authorities and, crucially, demonstrating cooperation to the American president, Donald Trump. On February 4th, she announced the deployment of 10,000 additional members of Mexico’s National Guard to the border, a move that led Trump to temporarily delay his threat to impose tariffs on Mexican imports until early March.

The U.S. has also reinforced its side of the border. The Department of Defense has sent an additional 1,500 active-duty troops to counter what Trump has labeled a national emergency. Airborne surveillance has been increased to track cartel activity.

Yet, despite these military efforts, the effectiveness of such measures remains in question. A U.S. Drug Enforcement Administration (DEA) officer, who requested anonymity, acknowledges that additional border security is helpful but insists it is "not a panacea." "The cartels are resourceful," he explains. "They smuggle drugs using cars, trucks, planes, people, tunnels—whatever it takes."

That resourcefulness is regularly displayed in social media posts by Michael Humphries, the CBP official overseeing the Nogales crossing. His updates showcase the ever-evolving tactics traffickers employ, from drugs hidden in petrol tanks and spare tires to fentanyl tucked within hollowed-out stacks of tortillas or concealed inside truck axles.

Beyond fentanyl’s adaptability in transit, its ease of production compounds the challenge. "It can be manufactured in any kitchen," says Guillermo Valdés Castellanos, former director of Mexico’s national intelligence agency. More than 90% of the fentanyl seized in the United States is intercepted at legal entry points like Nogales, and it is overwhelmingly smuggled by American citizens—not by migrants. These realities suggest that while border security plays a role, it alone cannot stop the drug trade.

That said, reducing fentanyl smuggling is not an unattainable goal. After years of rising numbers, fentanyl seizures at the U.S.-Mexico border fell in 2024, dropping by 21% from 12 tonnes in 2023. Additionally, the number of deaths attributed to synthetic-opioid overdoses in the United States declined by about 30% in 2024—the first such drop in over a decade. Carlos Matienzo of DataInt, a security consultancy, attributes these declines not to military deployments but to shifts in health policies, tighter controls on production, and the grim fact that many fentanyl users have already succumbed to the drug’s deadly effects.

Sheinbaum’s military deployment is more about "signaling to Americans that we’re willing to help," says Matienzo. Corrales, the public safety commissioner, concurs, noting that Mexico has not fundamentally altered its fentanyl-combat strategy. To move beyond symbolic gestures, the United States and Mexico would need to collaborate on dismantling drug cartels while simultaneously enacting policies to curb fentanyl demand in the U.S.

David Hathaway, sheriff of Santa Cruz County, Arizona—where Nogales is located—questions the necessity of increased military presence, arguing that it is more disruptive than beneficial. "People need a change of heart," he says. "We cannot legislate morality."