Originally Posted by
davidciani
Its really a question of what "risks" they are trying to protect against.
Its commonly understood that It wouldn't be possible to hijack an aircraft like they did on Sept. 11 again due only to the increased cockpit security and the new "attitude" about hijackers (previously it was: comply with the demands and everything will be all right). The risk that commercial airliners will be used as weapons of mass destruction has been successfully mitigated.
What are we left with? The plane and the people on it. What are the major risks? Explosives and someone with a firearm. These risks are present everywhere there is a large group of people in a relatively small space.
Even then, let us assume that they can with 100% certainty, remove any and all weapons and explosives from the passengers entering the airport(regardless of the time, cost, manpower and abuse this would take). We are then still left with the fact that a tewowist can access the terminal or aircraft with whatever weapon/explosive he/she wanted, as one of any variety of employees, to provide to an accomplice who came through security, with valid id and boarding pass.