What happened exactly to Lt. Rossi ? We are not told at the end

I believe he committed suicide. He was under stress and the colonel put him “against the wall”, without any acceptable option with honor. Inclusive he delivered his diary to his friend to be sent to his father. But it is just my opinion since the movie never discloses his fate.

Regards,

Claudio

I think that he was executed. In the scene where the father goes to the colonnel's house for the first time, the colonnel says something like "We all think that we did the right thing" which made the father ask "What do you mean?". I interpreted this as meaning that they shot him. He was given two choices, that is, comply to the orders or commit suicide. I think that he did not choose any of them.

I also thought he was executed...perhaps for disobeying orders and treason or something i.e. passing info to that communist teacher.

To me it seemed clear that the colonel had him executed. I inferred this from the interaction of the colonel with Rossi's father. The execution would not have been in accord with army rules hence the 'missing in action' disclaimer. I suspect that the colonel would have wanted to cover what he perceived as treachery within his ranks too.

I give my respect to those who have earned it; to everyone else, I'm civil.