By now, anyone who does not live in a cave, and everyone who does, is aware of the American TSA's policy of putting passengers through the Scylla of nude scanning or the Charybdis of "enhanced" pat-downs, which involve breast and genital contact. What do mathematical laws have to say about these new "safety" measures preventing anything?
According to U.S. government statistics, there are 620 million domestic passengers per year. The average number of flights per trip is about 1.5, so there are 410 million gate entries. At 10.8 million domestic flights per year, there is an average of 86 on board.
Let us generously stipulate that there is an average of one terrorist incident per year that is not stopped by current security practices, a 0.75 probability that the nude scanners and enhanced pat-downs would preempt these incidents and a 0.5 probability of a successful attack once the terrorist is on board, given technical glitches and vigilant passengers. The probability of dying in an attack that would have been prevented by the new measures is thus 8x10 to the negative eighth power.
In other words, Americans are having their genitals and breasts imaged and groped, and TSA employees are being made to execute said imaging and groping, in order to prevent an outcome for which the odds are less than half that of dying by lightning strike!
By contrast, the odds that both pilots on any given flight are alcoholics is 630 times higher, and the odds that at least one of the pilots is an alcoholic is a whopping 180,000 times higher. If this new "safety" measure is not impractical, nothing is.
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