"Clever terrorists can use innovative ways to exploit vulnerabilities. But don’t forget that most bombers are not, in fact, clever. Living bomb-makers are usually clever, but the person agreeing to carry it may not be super smart. Even if “all” we do is stop dumb terrorists, we are reducing risk." [TSA blog 21 October 2008]
In a reply to Bruce Schneier, Hawley adds
"Thanks for not taking a shot at me on my risk management point that even if we are just stopping dumb terrorists, we are reducing risk. You didn’t go for a clever rhetorical gimme, but instead raised the good point about transferring risk to outside the airport environment. That is a worthy discussion for another time." [Schneier on Security 28 October 2008]
Okay, here is a clever rhetorical gimme: the Atlantic has launched a New Contest: Can You Out-Lame the TSA?
Meanwhile the clever terrorists innovate.
"Intelligence shows that terrorists innovate in explosives formulas as well as the way they would bring them onboard an aircraft. That won’t change any time soon. If liquid restrictions are eased eventually it will be because of improved process and technology, not diminished threat." [TSA Blog 24 October 2008]
In other words, the effect of security theatre (Hawley doesn't admit that it is theatre of course, but then we wouldn't expect him to) is to force terrorism to evolve - to develop not only more clever terrorists but also less detectable tactics. Which in turn forces the TSA to acquire more and more expensive technology. The TSA blog is called The Evolution of Security.
But what about the Insecurity of Evolution? If the TSA were only facing a short-term threat there would be no reason to worry about the evolution of the threat over time, but that's obviously not the case. The requirements facing the TSA keep changing, and the TSA response is just to add more things to an already cumbersome and costly system. Things that were implemented incrementally in a series of panic responses to various incidents are now a permanent feature of our air travel experience (except for those wealthy enough to fly on private jets) - first shoes, then liquids, who knows (apart from the clever terrorists) what further troubles will be added in future?
At some point in the curve, air travel simply becomes non-viable. Bruce Schneier points out that the terrorists could easily switch to other targets. But more importantly, I hope travellers will switch to other modes of transport. At present, the only conceivable reason I can think of for flying from London to Paris is because the train is too expensive. But if air travellers were forced to pay the true cost of the security theatre, instead of its being funded by the tax-payer, then trains would start to look a lot more attractive.
See also Jeffrey Goldberg, The Things He Carried (Atlantic, November 2008) via Bruce Schneier