The root cause of the brutal competition for control of cities such as Ciudad Juárez in Mexico is the necessity to control access to the limited number of border crossings. The high levels of violence in border towns have led to calls from some people in the United States for crossings to be shut down. Yet economics suggests the opposite: by opening more of them, each would become less valuable, and less worth fighting for. True, it would give cartels more opportunities to smuggle their drugs into the United States. But clampdowns on supply have tended to have little impact on the total amount of contraband being smuggled, or on the drugs’ price (see Chapter 1). Opening more border crossings could reduce the amount of fighting, with little impact on the American illegal-drugs market.