I haven’t written anything about the suicide bombing at Moscow’s Domodedovo Airport because I didn’t think there was anything to say. The bomber was outside the security checkpoint, in the area where family and friends wait for arriving passengers. From a security perspective, the bombing had nothing to do with airport security. He could have just as easily been in a movie theater, stadium, shopping mall, market, or anywhere else lots of people are crowded together with limited exits. The large death and injury toll indicates the bomber chose his location well.
I’ve often written that security measures that are only effective if the implementers guess the plot correctly are largely wastes of money — at best they would have forced this bomber to choose another target — and that our best security investments are intelligence, investigation, and emergency response. This latest terrorist attack underscores that even more. "Critics say" that the TSA couldn’t have detected this sort of attack. Of course; the TSA can’t be everywhere. And that’s precisely the point.
via Schneier on Security – Domodedovo Airport Bombing. It sounds silly but it’s an key idea, the TSA can’t be everywhere.