With the TSA's favorite new toys the body imagers becoming a big issue right now (rightfully), I think it's time to unleash this little rant I've been refining for years (as they get dumber).
First, a note on suicide attacks.
Since a four-pack of suicide attacks via airliners were the event that kick-started this circus of stupid, it's not surprising that they've been where a lot of people focus.
The only way to try this which can be stopped is like the 9/11 attackers did, where they forced their way in to the cockpit and took control of the aircraft. There are two reasons this can't happen again. One is the reinforcement and regular locking of cockpit doors. The other is the awareness of passengers. If such an attack was ever tried again, even if they gained control of the plane it would be Flight 93 in seconds.
Bomb-based attacks can not be stopped ever. If someone is going to blow themselves up anyways, they now have a full set of cavities within which can be stuffed with large amounts of an explosive of their choice. Unless we're going to start cavity searching everyone who wants to fly (to any TSA employees reading this, that's sarcasm not a suggestion), it can not be prevented. Even if one could detect the human bomb at a checkpoint, they could just detonate right there and still have their desired effect.
Now that we're past suicide attackers, we're left with two tasks:
1. Keep unattended bags from getting on the plane.
2. Keep people from carrying dangerous weapons on board which could be used in a traditional hijacking.
The first is obvious, ensure any bombing would have to be a suicide bombing (which we already covered) by making sure that any bags on board belong to a passenger also on board.
The second weighs heavily on proper application of the word dangerous. This does not mean anything which could potentially be used as a weapon. This means anything that actually makes any sense to use as a weapon. We haven't seen any evidence for movie ninja grade weapons training among the types that have tried to hijack a plane, so while I'm sure Chuck Norris could kill 10 men with the scraper on a set of nail clippers that still doesn't mean it makes any sense to take them away from passengers. If it requires careful use to be of any concern, again the Flight 93 principle applies. There are more passengers than there would be attackers in any air travel situation, so as long as we can keep the guns and big blades off the planes any would-be attacker would easily be overwhelmed even by a small number of untrained individuals, much less if there was a trained air marshal or any current or former law enforcement or military on board.
Both of those duties can easily be filled without any of the invasive "security" the TSA wants us to believe we need, and were being filled quite nicely by their predecessors. We hadn't thought of the suicide-plane attack, so they got us by surprise, but it was a one-shot trick. Everything else either can be stopped with traditional security or can't be stopped at all.
As a final note, please everyone remember that more people died this year in car accidents in America alone than have died in all terrorist acts in recorded history. Use some perspective. In terms of threats that matter to an average American, terrorism is near the bottom. Stop worrying about it. And if you're a would-be terrorist, please steal a TSA uniform and shove some C4 up your ass. If we're going to keep reacting in fear from whatever the last attempt was, let's at least get some TSA agents being cavity searched for the good of the people.