I don't think the analysis is that clearcut as to whether the towers would still be standing. Nobody got into the cockpit of the airplane that didn't hit Tower 7, but it isn't still standing.FICU wrote:Had the doors been reinforced and locked the jets would not have been taken over, the twin towers would still be standing, and the world would probably be a little different today.photofly wrote:I don't think the unlocked cockpit doors themselves caused anyone to die - it was the hijackers.
You are right that if the doors had been locked, another means of gaining control over the aircraft would have to have been found. It may have been concluded that another means couldn't have been found and that the destruction of the three towers could not be accomplished. In the event, the doors weren't locked and two airplanes struck two towers. Whether that was what caused the collapse is very much in doubt.
I do believe cockpit doors should be secured as I accept the logic that there is much greater danger from 150 passengers having access than there is from one pilot locking out the other one to pull something like this off.