This U.S. State Department fact sheet discusses narco-trafficking and how it relates to terrorism. "The nexus between crime and terrorism has received much attention in the post September 11 world. [...] But how strong is the complicity of criminal networks with terrorist organizations today beyond the well-known narco-terrorism cases? And what trends around the world are we seeing today and what lessons have we learned that are applicable today, especially in our own backyards? Given that drug money often fuels other crimes, what is the current situational awareness related to the impact of narco-corruption and narco-trafficking in the war on terrorism in communities across the Western Hemisphere? Over the past decade, drug trafficking, transnational gangs, and other criminal organizations have grown in size and strength. They aggressively seek to undermine and intimidate government institutions in Mexico and Central America, compromise municipal and state law enforcement, and weaken governments' ability to provide public security and advance the rule of law."
U.S. Department of State: http://www.state.gov