In recent years Mexico has demonstrated the capacity to cultivate, process, ship, and transship vast quantities of illegal narcotic drugs. Such activity has traditionally been geared to the realities of domestic poverty, enormous profit, and American demand. Mexican marijuana dominated the U.S. market until quite recently. More importantly from the American viewpoint were the tons of Mexican heroin which saturated U.S. cities in the mid-1970s. Furthermore, Mexico is still the source of vast quantities of psychotropics and an increasingly popular conduit for South American cocaine.
According to Craig (1978), U.S. officials long sought to convince their Mexican counterparts that the key to any effective antidrug program lay in eliminating the illicit product at the source. Until such time that herbicides were applied on a massive scale against marijuana and opium poppies, they argued, the annual Mexican campaign would prove an exercise in futility.