After the FBI arrested a man for plotting to attack the Washington DC Metro - he signed on to an imaginary plot concoted by federal law enforcement - local transit police decided they may start searching passenger bags. Will Wilkinson reacts:

How does this make sense? The feds didn't unveil an unsuccessful terrorist plot. They unveiled a man's willingness to join a fabricated plot. But let us suppose that Mr Ahmed had signed on to an honest-to-goodness mass-murder conspiracy, and that this intrigue is now exposed and its principals rounded up. The chances of an attack are now higher or lower? There is now more or less reason for police to nose through the personal belongings of law-abiding citizens? I say: lower, less.

Here's the reasoning at work:

If we learn about a terrorist plot, it's evidence that police need more power so that they can keep us safer. A lack of intelligence about terrorist plots is evidence that police need more power to find out how safe we really are. A successful terrorist attack is evidence that police don't have enough power to fight terrorists. Whereas the successful arrest of a terrorist is either evidence that police haven't yet been given enough power to eliminate terrorism, or that the power we've given police is working and we should give them more power so we're even safer.

Regardless or facts, events, or reality, the right answer is always that we're to give up a bit more liberty, because, you know, terrorists.

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