Reply #37: You bring up an obvious interesting point....

[wadestock]

Any lame brain terrorist can now conceive of a plan to take them out AND use their weapons now.

You simply stage a wacko situation like what just happened.
The marshals reveal themselves as wanting to plug the wacko.
Since the protocol is plugging the guy with guns, then this takes their attention to that guy and with their weapons drawn.

That guy moves into position so that his co-terrorists can grab the Marshal's weapon....and if the wacko actor takes the fall...hey the terrorists don't mind losing people like that.

They now have much more probability of success jumping the marshal or two now.

People won't participate in helping the marshals now because of the risk of getting shot.

The use of deadly force ON BOARD and taking people out like this with guns is thus a wacko situation that leads to many many problems.

Whoever conceived of this wasn't thinking.
You'd be better off simply gasing the entire compartment.