The soldiers that didn't come back were the heroes. It's a roll of the dice. If a bullet has your name on it, you're a hero. If you hear a bullet go by, you're a survivor.
There is an electric fire in human nature tending to purify - so that among these human creatures there is continually some birth of new heroism. The pity is that we must wonder at it, as we should at finding a pearl in rubbish.