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These days, policymakers want the U.S. military to contain China; transform failed states into stable democracies; chase terrorists; train various foreign militaries to chase terrorists; protect sea lanes; keep oil cheap; democratize the Middle East; protect European, Asian, and Middle Eastern states from aggression; spread good will through humanitarian missions; respond to natural disasters at home and abroad; secure cyberspace, and much more. For the supporters of such missions, the military forces and budget needed to pursue these goals can never be enough. But the relationship between all these objectives and the proper mission of the Department of Defense to protect Americans is tenuous.