Most coca is grown in Colombia, Peru, and Bolivia. The farmers, for whom it is a relatively well-paying crop, harvest and dry the leaves, which are then processed into coca paste. Cocaine base is extracted from the paste in informal laboratories. Further processing produces cocaine hydrochloride, a white powder, which is exported. Once in the United States, the cocaine is cut (diluted) with ingredients such as lactose, and sold or further processed into crack.
Import and production have been controlled by enormously powerful cartels such as the Medellín and Cali cartels in Colombia; the highly armed cartels have infiltrated governments and corrupted officials and have been held responsible for assassinations of public officials. Drug trafficking reached the highest levels of government and was at least in part responsible for the U.S. invasion of Panama in 1989 and the arrest and subsequent conviction of Panama's de facto leader, Manuel Noriega.