“one underappreciated mistake has been Washington’s long-running effort to suppress the cultivation of opium poppies in Afghanistan and, in turn, the production of heroin and other opioids. The campaign most likely had little effect on the amount of poppy grown. Instead it shifted cultivation to Taliban-controlled territories, bolstering the militia’s revenues.”
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“American efforts to suppress poppy cultivation, either through direct eradication or through incentives to grow other crops, failed to account for the basics of supply and demand. Suppression policies focus on shrinking supply, which means a fixed quantity of opium will become more expensive to produce. These policies involve a mix of threats to destroy poppy fields and the provision of resources (such as fertilizers) to encourage farmers to cultivate other crops. But if demand is not very sensitive to price increases, the quantity demanded will change little in response to the reduction in supply.”