Most of these programs have emphasized supply reduction tools, particularly drug crop eradication and interdiction of illicit narcotics, and have been designed on a bilateral or subregional level. Many would argue that the results of U.S.-led drug control efforts have been mixed. Temporary successes in one country or sub-region have often led traffickers to alter their cultivation patterns, production techniques, and trafficking routes and methods in order to avoid detection. As a result of this so-called “balloon effect,” efforts have done little to reduce the overall availability of illicit drugs in the United States. In addition, some observers assert that certain mainstays of U.S.-funded counterdrug programs, particularly aerial spraying to eradicate drug crops, have had unintended social and economic consequences.

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