In the wake of the London bombings, New York City is now searching the bags of subway riders. As you might expect, this is provoking the usual cluster of perverse reactions. Someone on Air America, the liberal talk radio network, suggested that riders carry many bags to confuse and irritate the cops. Mayor Michael Bloomberg, normally a sane fellow, has ordered that the searches be entirely random, to avoid singling out any one ethnic or religious group. So if someone fits the suicide bomber profile—young Muslim male, short hair, recently shaved beard or mustache, smelling of flower water (a preparation...