A PERSON WHO is shown a brand new gun will immediately recognize it as a weapon—a dangerous piece of equipment with the power to maim or kill. If that same person is shown a shiny new automobile, the reaction will be vastly different. He or she may feel admiration, excitement, desire, or envy. But it is a rare person who will immediately recognize the car as a destructive weapon. Yet, as Sergeant David Williams of the Monroe, North Carolina, police force puts it, "A person can die whether he ate a bullet from a nine-millimeter or from a 3,000-pound vehicle." 5 In fact, far more teenagers are killed by cars than by bullets.

In the United States, at any given moment there are millions of three-thousand-pound vehicles weaving through crowded city streets at thirty-five miles per hour...