Drug prohibition has bred an amazing amount of violence in Mexico, especially since the Mexican government began its latest completely unsuccessful crackdown. Dan Kumar, chief of international affairs for the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives, says that that the drug traffickers have turned even more violent in a vicious war to control the drug routes to the U.S., that they have steadily increased their use of explosives (a mix of military ordnance and homemade grenades) in the past two years, and and there is reason to expect more of this type of violence.