I don't know how long it will take me to fully understand the magnitude of this disaster. I am still numb. Who would have thought a single plane could take out one of the tallest buildings in the world?
In any case, I think the assumption going forward now has to be that a hijacker is on a suicide mission and will use a plane as a guided missile. So, yes, I would fight back if put in such a situation. It is something new to think about whenever I fly in the front of the plane, just as I now review my responsibilities when I sit in an emergency row.
Obviously, I pray that the authorities improve aviation security so that the likelihood of such an on-board event occurring is minimized. But if it does, I would also hope that the pilots keep the cockpit secure and stay in control of the plane.