The Mexican Drug War is an armed conflict taking place between rival drug cartels and government forces in Mexico. Although Mexican drug cartels, or drug trafficking organizations, have existed for a few decades, they have become more powerful since the demise of Colombia's Cali and Medellín cartels in the 1990s. Mexican drug cartels now dominate the wholesale illicit drug market in the United States. Arrests of key cartel leaders, particularly in the Tijuana and Gulf cartels, have led to increasing drug violence as cartels fight for control of the trafficking routes into the United States.
Mexico, a major drug producing and transit country, is the main foreign supplier of cannabis and a major supplier of methamphetamine to the United States.Although Mexico accounts for only a small share of worldwide heroin production, it supplies a large share of the heroin distributed in the United States. Drug cartels in Mexico control approximately 70% of the foreign narcotics that flow into the United States. The State Department estimates that 90% of cocaine entering the United States transits Mexico—Colombia being the main cocaine producer—and that wholesale of illicit drug sale earnings estimates range from $13.6 billion to $48.4 billion annually.Mexican drug traffickers increasingly smuggle money back into Mexico in cars and trucks, likely due to the effectiveness of U.S. efforts at monitoring electronic money transfers.
In early 2010, United States president Barrack Obama sent 1,200 US troops to the American/Mexican border, to help stop incoming drugs and to simply increase border security.