their separate priorities and strike out on their own, as New York’s police and fire departments did on 9/11. The result is suboptimization—individual units may perform splendidly in terms of their own goals, but the whole may add up to much less than the sum of the parts. This problem plagued Tom Ridge, who was named by President George W. Bush as the director of homeland security in the aftermath of the 9/11 terrorist attacks. His job was to resolve coordination failures among the government’s