Under the security cooperation agreement called the Merida Initiative, the United States provides military and law enforcement assistance to the Mexican government in support of efforts to combat drug cartels and organized crime. The United States and Mexico jointly developed this agreement in response to a substantial increase in drug-related criminal activity and violence on both sides of the border.
According to its mandate, the Merida Initiative aims to "disrupt organized criminal groups, strengthen institutions, build a twenty-first century border, and build strong and resilient communities." The bulk of the Merida aid consists of training and advising for Mexican counter-drug forces. However, the United States also provides some limited amounts of military equipment—primarily aircraft—and weapons in support of those efforts. In addition, under the Department of Defense's Foreign Military Sales program and the State Department's Direct Commercial Sales program, the United States also sells and authorizes private companies to sell military aircraft and weapons systems to the Mexican government for a variety of purposes, including counter-drug missions.
Importantly, military and law enforcement training and equipping is only one part of the $1.9 billion Merida Initiative; its original tactical focus on Mexican security forces has shifted to a more strategic capacity-building mission for Mexican security, judicial, and related institutions. While the program seems to be making headway with the security forces, the initiative's newer priority of building Mexico's institutions remains fraught with challenges, including funding shortages, changing administrations and policies, and corruption and intimidation from the drug cartels they seek to combat. Given these challenges, the jury is still out on the effectiveness of the initiative.