Security expert Bruce Schneier explains Why Smart Cops Do Dumb Things:
Since 9/11, we’ve spent hundreds of billions of dollars defending ourselves from terrorist attacks. Stories about the ineffectiveness of many of these security measures are common, but less so are discussions of why they are so ineffective. In short: Much of our country’s counterterrorism security spending is not designed to protect us from the terrorists, but instead to protect our public officials from criticism when another attack occurs.
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If someone left a backpack full of explosives in a crowded movie theater, or detonated a truck bomb in the middle of a tunnel, no one would demand to know why the police hadn’t noticed it beforehand. But if a weird device with blinking lights and wires turned out to be a bomb — what every movie bomb looks like — there would be inquiries and demands for resignations. It took the police two weeks to notice the Mooninite blinkies, but once they did, they overreacted because their jobs were at stake.This is Cover Your Ass security, and unfortunately it’s very common.
Airplane security seems to forever be looking backward. Pre-9/11, it was bombs, guns and knives. Then it was small blades and box cutters. Richard Reid tried to blow up a plane, and suddenly we all have to take off our shoes. And after last summer’s liquid plot, we’re stuck with a series of nonsensical bans on liquids and gels.
Once you think about this in terms of CYA, it starts to make sense. The Transportation Security Administration wants to be sure that if there’s another airplane terrorist attack, it’s not held responsible for letting it slip through. One year ago, no one could blame the TSA for not detecting liquids. But since everything seems obvious in hindsight, it’s basic job preservation to defend against what the terrorists tried last time.