I think most soldiers shouldn't be punished. They were fighting an unjust war, however they didn't commit war crimes, most of them at the least.
I agree that most of them shouldn't be punished...by us.Let the Lord make the decision.I think we are not invited to judge,especially not to the majority of them because we don't know how someone is guilty is.
Now,I'll comment bold part.
How is it possible not to commit war crimes when you are bombing everything that has nothing to do with the Army?Bombing hospitals,railways,trains,oil refineries,all kind of factories,bridges,electro-distribution network(even Chinese embassy),...etc.Everything that is country's economy and has any significants for life support was the target.That's the crime against humanity.
I can't remember who was the person who told the media something like that(I'm paraphrasing):"We should make their air dirty,so they can't breathe".I think it was some German politician or general,highly ranked.
And another thing.Even if they succeeded to damage the Army,it would be also a war crime,because that war is a crime,no meter what or who has been attacked.