Controls on handguns might cause some criminals to shift to the more lethal rifles and shotguns. The result could be a substantial increase in the number of homicides. Shifts by other criminals to knives would increase the injury rate. People no longer able to buy guns to protect themselves might experience increased fear, although it is unclear whether their risks of victimization would increase or decrease. Research indicating that a high proportion of citizens would not comply with gun control laws also suggests that this widespread noncompliance would cause the public to lose confidence in government and the criminal justice system and the financial costs of enforcing the law would be large. Criminals might shift their activities from commercial targets to the elderly and the poor, who would provide easier targets for unarmed offenders. Some types of gun control might generate costs to the nation's external security. Having many citizens owning or experienced with firearms reduces the need for a large standing army and also suggests to foreign enemies that an invasion of the United States would be met with extensive guerrilla warfare. These points suggest the need to evaluate the subtleties and consequences of any proposed public policy. Questions and answers, 13 references.