More than 6,000 Mexicans died in drug wars last year, and violence has surged recently as gangs battle the police and each other. But because of Mexico's strict gun laws, cartels have to get their weaponry from elsewhere: the United States. Ninety percent of guns recovered in Mexico originated north of the border, the New York Times reports—often from small dealers scattered along the border.
Mexican civilians need approval from the military to buy handguns, and high-powered rifles are illegal. The cartels enlist Americans to buy assault rifles from multiple dealers, then import them, often stuffed in the panels of cars. Arizona's attorney general compared the traffic to a "parade of ants." "It’s not any one big dealer, it’s lots of individuals," he said. "That makes it very hard to detect." (Read more Mexico stories.)