The requirement to present identification began during the unabomber scare when he threatened to detonate a bomb on a plane during a busy weekend. I believe the gov't had a list of possible suspects, and the idea was for the airlines to help the FBI catch him. His threat was a bluff so it did not work.

The airlines realized that the ID requirement added to their profits because it prevented people from transferring tickets, and resulted in wasted tickets and change fees. So the airlines kept this requirement.

The airlines will even tell you that ID is required by FAA regulations, which prior to Sept. 11 was an outright lie. It was only required by the airlines' own procedures. After Sept. 11 and the Patriot Act, ID may be requierd by law--I don't know.

The point is, the purpose of the ID requirement in teh airlines' mind is not for security but as an indirect revenue device and to hassle passengers.