Yesterday's tragic shooting in a Colorado theater reveals an awful flaw in the current policy, supported by both Obama and Romney, to reduce gun violence. It has been thought that the way to do so is to reduce the number of guns. In the interests of protecting the most vulnerable members of the population, school and university campuses, along with post offices, banks, and other important facilities, have been designated as gun-free zones. These efforts, although put into effect with the best intentions, are horribly misguided.