[H]ow far are we willing to go to prevent weapons or bombs from getting on airplanes? In the past decade, terrorists on airplanes have killed just about 3,000 people — all on one day. Even if the Christmas Day bomber had succeeded, the number would be under 3,500. Those are horrible deaths. But in that same period, more than 150,000 people have been murdered in the United States. We haven’t put the entire U.S. on lockdown — or even murder capitals like Detroit, New Orleans and Baltimore