You stated earlier that if a guy claims to have a bomb while taking over an airplane, and I jump him to try to take the bomb away, or stop him from blowing the plane up, it's somehow MY fault if HE (the guy with the bomb, the one who committed several illegal acts) blows the bomb up, because I don't trust someone who says, "just do what I want you to and I won't hurt you".
This earlier statement puts you right in the camp of "if a criminal STEALS a gun from your home, YOU'RE responsible for any acts committed with the gun."
You go right ahead and keep on trusting those people who promise not to hurt you, and I guess I will be responsible when the plane I'm on blows up because I didn't trust the guy with the gun to my head.
The outcome was almost certain death (chance of eliminating or negotiating with the hijackers and safely landing the plane were slim to say the least). The circumstances of the terrorists' plans were understood by the passengers, they could only intervene and diminish the impact of the terrorists' plans.
The passengers who intervened are called heroes and it is noted that they gave their lives. If an altercation inflight had caused a bomb to go off, it may never be determined exactly why the terrorists "set it off" at that place or time.
I figure a person who brings a bomb on a plane as being someone committed to using it. The only legitimate bombs I can recall either went off in flight, were detected before the flight, or were used in "negotiations" on the runway (the incident I recall ended with the plane blowing up with passengers in front of cameras). It doesn't seem likely that they will surrender their bomb if they get their way (e.g. prisoners released).
I have no problems calling these thugs terrorists (they have attacked but hidden their motives, no one has stepped forward yet to take responsibility - thus the "cowards" label still fits). I've read several press reports that called them "freedom fighters", if that means they fight freedom then I agree but they certainly aren't fighting for freedom. Isolating an oppressive regime from outside influences doesn't beget anyone freedom.
One final bit of semantics, these are being called hijackings but since the planes were being flown by the "hijackers" with no intent to land, they were either "plane-jacking" or more succinctly "joyriding". I'm not familiar with other circumstances where hijackers killed the pilots and took over flight in air.