Squeezing the balloon?

Drug policy scholars generally agree that coercive attempts by the United States to reduce drug supplies from abroad have negative side effects. This article confirms that US coercion has made a bad situation worse. However, it also argues against oversimplified statements about the creation of side effects. The empirical focus is on the Air Bridge Denial Program, a US-sponsored attempt from the late 1980s to 2001 to reduce aerial drug trafficking in South America. A causal mechanism is developed that helps to understand and explain how air interdiction contributed to the displacement of coca cultivation from Peru to Colombia, an increase in Peruvian and Bolivian cocaine production, and a diversification of trafficking routes and methods. The analysis also examines contingent conditions, empirical black boxes, and alternative explanations. A complex empirical picture means that the popular metaphor of a balloon whose air, when squeezed, simply moves elsewhere is misleading. Although US-sponsored air interdiction has contributed to displacement, other factors have played a role as well.