“Trump’s contention that Mexico and Canada could “easily solve” the drug trafficking problem was equally dubious. For more than a century, politicians have been promising to “stop the flow” of illegal drugs, and they have never come close to achieving that goal—not for lack of trying, but because the economics of prohibition doom all such efforts.
Prohibition allows traffickers to earn a hefty risk premium that provides a strong incentive to find ways around any barriers that governments manage to erect. Drugs can be produced in many different places, and they can be smuggled into the country in a wide variety of ways. Any serious effort to prevent drugs from entering the United States would entail intolerable disruption of travel and trade, and it still would not succeed. That challenge is magnified in the case of a highly potent drug like fentanyl because large numbers of doses can be transported in small packages that are hard to detect.
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Since Canada accounts for only a tiny percentage of fentanyl entering the United States, “flood” seems like an exaggeration. In any case, it is not clear what would qualify as “adequate steps” or “satisfactory resources” as far as Trump is concerned. Taking Trump at his word, there is no such thing, because there is nothing that Canada or Mexico can do that will be sufficient to achieve the impossible goal of stopping illegal drugs from entering the United States.”