The Economist is hosting a debate between Bruce Schneier and former TSA honcho Kip Hawley, on the proposition "This house believes that changes made to airport security since 9/11 have done more harm than good." I'm admittedly biased for Bruce's position (he's for the proposition), but it seems to me that no matter what your bias, Schneier totally crushed Hawley in the opening volley. The first commenter on the debate called Hawley's argument "post hoc reasoning at its most egregious," which sums it all up neatly.
Here's a bit of Schneier:
Let us start with the obvious: in the entire decade or so of airport security since the attacks on America on September 11th 2001, the Transportation Security Administration (TSA) has not foiled a single terrorist plot or caught a single terrorist. Its own "Top 10 Good Catches of 2011" does not have a single terrorist on the list. The "good catches" are forbidden items carried by mostly forgetful, and entirely innocent, people—the sorts of guns and knives that would have been just as easily caught by pre-9/11 screening procedures. Not that the TSA is expert at that; it regularly misses guns and bombs in tests and real life. Even its top "good catch"—a passenger with C4 explosives—was caught on his return flight; TSA agents missed it the first time through.
In previous years, the TSA has congratulated itself for confiscating home-made electronics, alerting the police to people with outstanding misdemeanour warrants and arresting people for wearing fake military uniforms. These are hardly the sorts of things we spend $8 billion annually for the TSA to keep us safe from.
Don't be fooled by claims that the plots it foils are secret. Stopping a terrorist attack is a political triumph. Witness the litany of half-baked and farcical plots that were paraded in front of the public to justify the Bush administration's anti-terrorism measures. If the TSA ever caught anything even remotely resembling a terrorist, it would be holding press conferences and petitioning Congress for a bigger budget.
And some of Hawley:
More than 6 billion consecutive safe arrivals of airline passengers since the attacks on America on September 11th 2001 mean that whatever the annoying and seemingly obtuse airport-security measures may have been, they have been ultimately successful. However one measures the value of our resilient society careening through ten tumultuous years without the added drag of one or more industry-crushing and national psyche-devastating catastrophic 9/11-scale attacks, the sum of all that is more than its cost. If the question is whether the changes made to airport security since 9/11 have done more harm than good, the answer is no.
Risk management is second nature to us. At the airport we see a simple equation: "I pay a cost in convenience and privacy to get reasonable certainty that my flight will be terror-free." Since 9/11, the cost feels greater while the benefits seem increasingly blurred. Much of the pain felt by airport security stems from the security process not keeping up with its risk model. In airport security, we have stacked security measures from different risk models on top of each other rather than adding and subtracting security actions as we refine the risk strategy. This is inefficient but it does not create serious harm.
Schneier adds, "I'll take suggestions for things to say in Part III."