So here's on of my pet peeves: we want to think we're rational, then we go do stupid stuff like this (click image for full-size):
How rational is it to spend 25 times as much on something that is almost 2000 times less likely to occur? Answer: it isn't.
And if you are tempted to say something like "Yeah, but we got Bin Laden, the war is working!", well, then, I suggest you read The Starfish and the Spider. In any case, even if we did stop terrorism (which we didn't), we've got much bigger daily threats to our lives that we're ignoring. This graph hopefully puts one of them in perspective.