+1 it has always confused me too - security, while imperfect, does make a difference

The Flight 93 movie making heros out of people resisting hijackers (and making it known that hijacking wasn't just a diversion to Cuba anymore) was the only thing we ever needed to fix the system.

It's not proof of anything, including not proof that it works. The catalytic converter was stolen off of my father's car, was replaced, and then was stolen again. When it was replaced the second time, he very seriously considered paying for anti-theft devices to accompany its replacement. In the end, he chose not to purchase or install any anti-theft devices. His catalytic converter hasn't been stolen since. Just as this is not proof that choosing to do nothing has prevented subsequent theft, if he had purchased a device, the absence of a subsequent theft would not be proof of its effectiveness.