Gene Healy has an amusingly written but smartly biting column in the Washington Examiner in which he notes that “when I tell my right-wing friends that al Qaeda isn’t an ‘existential threat’ to the United States — that we don’t need to suspend our Constitution to keep ourselves safe — they tend to look at me like I’m some sort of communist.” Conservatives nowadays are all too willing to trade liberty for security, but he notes that this isn’t a fair trade. No one should deny the enormity of what happened on September 11, 2001, but he points out that in general, terrorists are rarely successful in achieving their goals.

The Japanese cult Aum Shinrikyo had roughly a billion dollars devoted to developing chemical and biological weapons, the most sophisticated such program in the history of terrorism. But when it released sarin gas on the Tokyo subway in 1995, it only managed to kill 12 people.

Some might say that when we argue about how to respond to terrorism, the terrorists win. But actually, it doesn’t take much for the terrorists to score at least a minor victory against the country they hate so much.

Terrorists bank on overreaction. As Osama bin Laden put it in 2004, “All that we have to do is to send two mujahedeen to the furthest point east to raise a piece of cloth on which is written al Qaeda, in order to make the generals race there to cause America to suffer human, economic, and political losses.”

Adam Gadahn, the U.S.-born al Qaeda spokesman, recently called for more “lone-wolf” strikes, because “even apparently unsuccessful attacks on Western mass transportation systems can bring major cities to a halt [and] cost the enemy billions.”

As someone who traveled back to the U.S. on an international flight just a few days after a Nigerian national lit his underwear on fire, I certainly know what Gadahn is talking about. Slow-moving security lines in a mid-sized airport in Canada led to delayed flights; multiply the effect by the number of airports worldwide serving the U.S. This is why lines moved at a snail’s pace: Every item in the one carry-on I was allowed was gone over meticulously by hand, with every item of makeup opened and closely examined, every piece of plastic and paper in my wallet flipped through. Each person in line was patted down. I saw in front of me a little girl, probably around three or four years old, in tears because a stranger insisted on touching her all over. The problems didn’t end once we were on our planes—we weren’t allowed even a book to read during the last hour of our flights.

While media coverage stoked fear (though the writers of this piece seem to acknowledge that if someone really wants to cause havoc, there’s not much billions of dollars in security can do about it), government officials used the incident to help their push for what one critic calls “digital strip searches.” (And keep in mind that a test conducted by the BBC showed that the plane would have landed safely even had the bomb gone off as intended.)

As Healy concludes, “when we overreact, we’re doing terrorists’ job for them.”