"Emmanuel Gustin" wrote

The vast majority of hijacks have not ended in crashes, but in
safe landings, and were resolved on the ground by negotiation
if possible, and in the worst case by security forces storming
the plane. Seems to me that the presence of the sky marshall
could perhaps prevent the rare event, but significantly increases
the probability that the more common event ends in disaster.

Pre-9/11, yes.

But the "Take me to Cuba" or "release our glorious leader from prison"
scenarios have changed. Now, the passengers and crew *must* assume that the
hijackers wish to commit suicide and mass homicide by flying the a/c into a
high value target on the ground. To assume anything less is foolish.

Pete