by Michael D’Antonio

About the author: Michael D’Antonio is a Pulitzer Prize–winning journalist who writes frequently about social issues.

A gunman shoots up a post office in New Jersey. Another attacks a restaurant in Texas. A rash of car-jackings strikes Georgia. Any rational person would be alarmed by these horrible crimes against innocent people. And we are. National polls consistently show that violent crime is one of America’s greatest concerns.

But we don’t need polls to tell us this. We know it when we stop at a crowded intersection and suddenly get the urge to lock the doors. We feel it when bloody images from the nightly news fill our minds.

We are right to feel afraid. When a sniper shoots a diner sitting near a...