Are these sorts of ethical dilemmas ever posed to people serving in the Military?

I often wonder about this, because there seems to be no shortage, in times of real crisis, to find a soldier willing to fling himself under the trolley (without needing to hurl a fat man) if need be.

Of course, this is something that is ingrained in the soldier's behavior during training, and it, at times, doesn't take.

Then, there are times when the military becomes filled with people who are willing to throw anyone onto that railroad track, as long as the math turns out correctly (more people saved than killed). It is an officer's job to do just that (and then order a soldier to do the actual throwing).

I guess this just shows that people are capable of having their normal morality either amplified or nullified depending upon the context. In some cases, there may be no morality to speak of in some classes of soldiers.

However, you do bring up an excellent point. Immediacy of the situation/decision. It is relatively easy for people to make dispassionate and rational decisions when they are not in the heat of the moment or more removed from the actual situation. I have found that it is a rare individual who can actually make a rational decision in the heat of the moment without considerable training (and not just mental training. It takes real simulation of the act for most people to learn just how they will react in such situations).