Also to address an issue that several people have mentioned about celebrites, the pope and the president having armed security. What world do you live in? Many of these people face daily threats; some serious, some not so serious. They are often very real targets, especially religious and world leaders. Most schools are not daily targets, most banks aren't even daily targets. Again it is not comparing apples to apples but apples to unicorns.
I'll bet there's a bank robbed everyday banks are open. The building at Ft. Hood was a no guns allowed building and the building wasn't guarded. There was a armed "police force on the base. There's hard targets ( the President ) and soft targets ( schools and other places that guns aren't allowed ). Airplanes were soft targets.