Let’s calm down for a moment and in Mark’s spirit, think about what’s really going on here. In 2008, there were about 800 million commercial (scheduled carrier) airplane trips from, in, and to the US, on about 11 million flights. In the decade since 2000 (traffic has been up and down, of course), let’s say 100 million flights. Of these, three were successfully used as terror weapons against non-passengers, a fourth was crashed, and six crashed in accidents with no or few survivors. If we just use the crude averages as a guide to probability, when you get on a plane, you are drawing one pea from a bucket of peas that contains four black ones (you die from terrorism) and six red ones (you die from something TSA has nothing to do with).
How big is this bucket? I did a little experimental research with the extra blackeyed peas I didn’t cook up for New Years: it’s 800 6400 gallons [thanks, Cardinal Fang – in comments], which is about six feet across and four feet tall. Full of peas, with ten killers among them, four terrorist. Is there anything that could make it worth reaching diving into this bucket, groping around, and picking one pea? Attitudes to risk vary, but I don’t consider myself especially courageous and I would do it for almost anything nice. I would do it for twenty bucks. I certainly did it repeatedly in order to get from A to B when there were only the six accident peas, without even thinking about it; I rode a motorcycle for years, for Pete’s sake (admittedly, in a very cowardly style). Four more death peas in that bucket hardly move the needle from where it was for “flying in general”.
But the four deadly 9/11/01 events used a strategy of taking control of airplanes whose cockpits were not secured, with knives initially deployed against the cabin crew. Since 2001, there have been no attempts to take over airplanes; it’s pretty clear that even if you get a weapon on board today, you might spill a lot of blood in the cabin but you are not going to fly the plane into a building, or even crash it. I think we can take the four black peas out of the bucket and replace them with two grey ones, representing those failed attempts to blow up the plane with non-metallic explosives (another was interdicted on the ground, before the plane even took off).
Inference: we should not be getting all bent out of shape about this very occasional occurrence. Language like “completely unacceptable” is just nonsense and very bad leadership: less is better than more, but as Mark explains, before we start acting as though all of human behavior should be dedicated to the purpose of “no chemical bombing attempts on airplanes, at all, not one single one, ever”, we need to do two things. The first is to treat the costs of different ways of further reducing the already minuscule, microscopic odds seriously, and not letting passengers read a book on their laps for the last hour of a flight is not a trivial cost (not to mention that it has absolutely nothing to do with real security: Abdulmutallab was too stupid to work his bomb at leisure in the toilet, but the next bomber probably won’t be). The three-little-bottles-in-a-plastic-bag rule is a non-trivial cost as well, in addition to being just dumb (no-one checks to see what liquids are in the bottles); two of them half full are plenty to blow out the side of an airplane. A lot of airplane security is about being seen to be worried about something passengers might or not be afraid of, not about making flying safe; it’s mendacious and damages the credibility of government, not to mention insulting our intelligence and wasting our time.
The second, much more specific, is to recall that one of the four 9/11 attacks was constrained to the airplane itself by passenger action, and both the bomb attacks were aborted by passengers, and to act on this lesson. Let’s go back to the knives for a minute: would you rather be on a plane where the only person with a knife (or a bomb) is the terrorist who got it through screening, and the air marshal with a heater is a twenty rows back or not on this flight…or on a plane where you and lots of other passengers have Swiss Army knives in their pockets? Would you think you could hijack a plane more easily by smuggling that knife or bomb kit on (or even a gun) if most of the passengers were equipped, or if most had been graciously disarmed by TSA? If we know the “no weapons” rule would exclude all weapons, it might make sense, but we know it doesn’t, and therefore enables the bad guy. Actually, I would feel much better overall if adult passengers were charged a few bucks extra if they were careless enough to fly without a pocket knife (guns are another story because using one in an airplane is so hazardous to the aircraft itself, and they are a lot easier to screen for).