The best in paranoid bureaucrats and genre fiction authors must be hard at work for the TSA. Remove your belt, remove your shoes, get used to minor indignity, "yes sir," "yes ma'am", little slips of paper saying your (obviously harmless, if one bothers to check the X-ray) bag has been rifled, have become the way of life for travelers. Need to urinate or grab a sandwich while awaiting a connection at the Kansas City airport? Be prepared to do the pockets, belts, shoes, doff-and-don dance; who knows what's been hidden in the urinal!
One thing egregiously overlooked is the contents of our bowels and bladders. Surely an exploding passenger would be ineffective, but what of mixing a bomb in the forward and aft lavatory. Ahmed, Ousman, Hillary, George, Dick, and Barack can all lift a leg in turn, the final flush stirs it up nicely, and down goes an airliner.
Homeland Security Threat Level Orange, anyone?