Would a plain old bombing really do those trillions of dollars of damage? A hijacking is what has the potential to cause massively disproportionate damage, and that is a solved problem (Not solved by the TSA though...).
Even so, let us imagine some alternate universe where non-TSA security adaptations have not solved hijackings... The measures the TSA has taken to prevent hijackings would not. Why don't they work? Well, what happens to you if the TSA finds the pairing knife you accidentally left in your carry on? They take it, throw it in a bin, and wave you through. The only thing a prospective terrorists is out is a knife and a plane ticket. Given their abysmal false negative rate, he will eventually succeed.
The TSA pretends to make us safe from yesterday's ploy. In reality they don't even do that. (To be clear, we are safe, but with no thanks to them.)
To be clear, it looks like there are two different questions being conflated here. The first is whether the TSA's procedures would help a prevent 9/11-style hijackings. I think everyone agrees that the TSA doesn't add much value in the single hijacker case, simply because passengers can probably overpower a single hijacker.
If the number of hijackers increases to, say, a dozen, then perhaps the TSA might help here, because a dozen men in the front of the plane armed with sufficient weapons might be able to hold off the rest of the cabin, and getting a sufficient number of serious weapons (and door-openers) though security might be too risky to make such an attack worthwhile. After all, a dozen terrorists might be more profitably used elsewhere.
The second question is whether the TSA's more onerous policies, like use of full-body scanners and bans on liquids, prevent fatal bombings of airliners (not hijackings). Clearly terrorists are not only interested in using planes as weapons, but simply causing them to crash by, say, detonating a bomb from the restroom. Here I postulate that the TSA may be doing some good by preventing terrorists from refining any one technology, but that's only one theory.
> The second question is whether the TSA's more onerous policies, like use of full-body scanners and bans on liquids, prevent fatal bombings of airliners (not hijackings).
The thing most people don't know is that the reaction of Acetone and Hydrogen Peroxide produces nothing but heat. If mixed in the bathroom out of the smell of anybody, it can be left in a bottle and looking like pure water. It will slowly crystallize acetone peroxide as the reaction occurs. Given enough time - like a 7 hour flight - you could have sufficient quantities of highly reactive acetone peroxide crystals that would likely go off at the slightest movement even while still in a liquid. So screw the bathroom, it's under any seat in any backpack.
Most people think of the anarchist cookbook method that uses an acid to form it, which works in creating DADP or TATP which are the more stable variants. However they require a lot of ice, and still take a lot of time anyway.
Even a water bottle full of the mixture would produce a sizeable amount of explosive (assuming using 30% hydrogen peroxide). The fucked up thing being I can grab a can of acetone and a can of hydrogen peroxide (wood stain remover) at home depot for under $20.
The only question is how do you get it in? Boil a bottle of water and you can pop the lid off it without breaking the seal, keep that in boiling water, refill the bottle with what you want, take the lid out and push it back over, when its cooled it looks like new. I've gone to enough concerts to know how to sneak a bottle of rum in.
I really wouldn't want to be on the plane when a guy was allowed to mix together two 1L water bottles to make almost a lb of primary explosives that detonate with almost twice the force of TNT.
> Boil a bottle of water and you can pop the lid off it without breaking the seal, keep that in boiling water, refill the bottle with what you want, take the lid out and push it back over, when its cooled it looks like new.
Make sure to label it "saline solution" and claim it as a medically necessary fluid (or any of the other numerous exempt fluids and gels) so that you can go over the 3.4fl oz limit. Hell, just call it your "enema solution". What TSA agent would look too closely at that?
If you want to do some sort of worth calculation on the TSA using cost of a terrorist attack, then you have to break it down by attack type. Damage done by the attack and probability of success both must be considered. Binary liquid bomb attacks are extraordinarily unlikely, extraordinarily hard to do successfully, and cause relatively little damage.
Terrorists are interested in airplanes for two reasons: they can be hijacked to great effectiveness (not anymore), and they know we react irrationally to threats to airplanes (this is what we should seek to fix). With both of these fixed, the threat terrorists pose to airplanes would be no more notable than the threat they pose to any other modestly sized group of people.
Re: a dozen terrorists with sufficient weapons/tools
Even assuming they could get these weapons/tools past pre-9/11 security, which is very doubtful, the chances of it working out the way they wanted are still absurdly small. What pilot would not fly the plane straight into the ground if the locked cockpit door was actually being breached? People know that hijackings are not survivable anymore. You are either killed or someone sits on a terrorists for a few hours, there aren't any other outcomes.
A dozen men with weapons sufficient to hold off an entire plane can do plenty of damage on the ground, and they don't even need to walk through a metal detector to do it: http://en.wikipedia.org/wiki/2008_Mumbai_attacks Why bother having a chance to kill a few hundred people on a plane when you can do the same on the ground?
Yet we don't see either being attempted...
Frankly, all of these threat scenarios are fantasies.
I think it was over 2 years ago but a guy on reddit pointed out that terrorists would obviously target the weakest link. He said something on the lines that instead of trying to hijack airplanes they'd just go blow up some mall or something. If my memory serves me well, I think they put a tracker on him for that comment.
Oh yeah, I remember that. I assume I'm already on plenty of watchlists for being moderately vocal about thinking the entire situation is bullshit. Maybe it's time I look under my car again.
The funny thing is I'm neither American nor in the USA, but I'm sure they've still got some intel on me (since USCIS does legally have my records anyway).
Even so, let us imagine some alternate universe where non-TSA security adaptations have not solved hijackings... The measures the TSA has taken to prevent hijackings would not. Why don't they work? Well, what happens to you if the TSA finds the pairing knife you accidentally left in your carry on? They take it, throw it in a bin, and wave you through. The only thing a prospective terrorists is out is a knife and a plane ticket. Given their abysmal false negative rate, he will eventually succeed.
The TSA pretends to make us safe from yesterday's ploy. In reality they don't even do that. (To be clear, we are safe, but with no thanks to them.)