A reader writes:

>>Yesterday I deliberately opted out of the back-scatter machine at Toronto airport so as to see what the enhanced pat-down is about. I must say I have thoroughly enjoyed the experience. It is akin to a full-body massage. Just to be sure that I am not the only one who has this unusual view, I posted my experience on Facebook, and immediately several of my friends concurred.

Oh, I forgot to mention that these friends of mine are all gay.<<

In the "but seriously now" category, I think it's worth reviewing why people disagree about intimate pat-downs and the like. The more I think about this, the more discouraged I am that there is any feasible resolution.

Disagreements about, you know, "ideas." I think there are three big ones here, though not usually discussed explicitly:

1) Direct versus indirect costs of terrorism. All security measures are justified relative to the direct terrorist damage they might prevent. The plane that would come down, the bomb that would go off. But anyone who's ever thought about terrorist movements realizes that the real damage is indirect -- it's the fear they induce, the (over) reaction they provoke, the costs they impose as a society tries to guard against repetition. That's what Osama bin Laden noted in a tape after 9/11 -- that on the cheap, his attackers had not simply killed 3,000 people but induced a response that will cost the U.S. trillions of dollars over a decade or more (if the costs of war in Iraq are included, as they should be). More on the topic here.

So people who say, we can't forgo any measure that might reduce risk, are concentrating on the direct threat of terrorism. Those who say, let's consider the distortions we're imposing on ourselves, are thinking of the indirect risks. It's hard to bridge these outlooks.

2) Prevention versus resilience. People who study terrorism -- or crime, or natural disasters -- also generally conclude that after a certain point, it's better to work on ways to recover from an attack, or limit its damage, rather than spend limitlessly toward the impossible end of reducing the risk to zero. The design of the Internet is an extreme example: it was built, in the Cold War era, to repair itself (by re-routing traffic) if some nodes were destroyed in an attack. Or air bags in cars: we try very hard to prevent crashes, but since some still occur, air bags make them less dangerous. Or: fortified cockpit doors in airliners. There could well be another terrorist who gets onto an airplane with weapons; but there will never be "another 9/11," because cockpit-door design, and alert fellow passengers, will keep hijackers from turning a plane into a missile.

As applies to airport security, this approach means trying very hard to keep dangerous passengers and cargo off airplanes -- but also thinking about how the same money, effort, social friction, etc might be used in "resilience" efforts. Which leads to:

3) The 'zero-risk' mentality vs 'acceptable' risk. Every society accepts some risks as part of its overall social contract. People die when they drive cars, they die when they drink, they die from crime, they die when planes go down, they die on bikes. The only way to eliminate the risks would be to eliminate the activities -- no driving, no drinking, no weapons of any kind, no planes or bikes. While risk/reward tradeoffs vary between, say, Sweden and China, no nation accepts the total social controls that would be necessary to eliminate risk altogether.

Yet when it comes to dealing with terrorism, politicians know that they will not be judged on the basis of an "acceptable level of risk." They know that they can't even use that term when discussing the issue. ("Senator Flaccid thinks it's 'acceptable' for terrorists to blow up planes. On Election Day, show him that politicians who give in to terror are 'unacceptable' to us.") And they know for certain that if -- when -- a plane blows up with Americans aboard, then cable news, their political opponents, Congressional investigators, and everyone else will hunt down any person who ever said that any security measure should be relaxed.

This is the political tragedy of "security theater." In reality, we do accept a greater-than-zero risk of death from terrorist attack. Otherwise, we'd never fly -- or would strip everyone nude before boarding, do cavity searches, and carry no cargo. We accept the bargain for efficiency reasons (I'm not going to get to the airport six hours early to be searched). We accept it on "price of liberty" grounds (I'm not going to strip naked). But politicians can't come out and say that any risk is acceptable. Nor can they take the risk themselves of saying that security-theater rituals should be dropped, because of the risk of being blamed when the next attack occurs. Thus security-theater is a ratchet. You can add it, but you can't take it away.

When we can't talk about what we're really doing, and when we penalize politicians for speaking the truth, we're asking for trouble. Of the sort many people will encounter at the airport tomorrow -- and in months ahead.

I was going to have a second section, about odd political alliances on this issue, but I'll save that for later. Instead this bonus reminder point: this is not about individual TSA agents, who have an impossible and increasingly unpleasant job to do; and it's not even about the TSA's leadership, which is not really empowered to make risk/reward tradeoffs. It's about political leadership -- and why neither legislators nor the executive seem able to provide it here.

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