One minute you set your rifle down against a tree to go take a leak, the next minute you realize it's nowhere to be found. Your rifle — the one thing you cannot lose during this training exercise — is missing. Here is what goes through your head in that moment:
Oh my God. Oh God. Oh no. I'm doomed. My life is over.
Well, maybe my platoon sergeant won't notice.
If I just pray enough, it will appear and everything will be just fine.
Jones over there isn't paying attention. Maybe I can steal his.
Crap, that won't work. My rifle is serialized, so they are going to know it's a different number.
Ok that's it. I'll fake an injury and tell the Lt. I fell down and my rifle was lost in a swamp.
No that's not going to work. There are no swamps anywhere. Oh my God. Oh God. I'm doomed. My life is over.