My dad was in Korea and he never really talked about the war, but years after he died, my mom told us that he said that after what he saw there, there can be no God. And he was there for only a few months.
The World Wars were a large impetus for the victory of atheism/agnosticism in Europe--though it had been gaining in momentum since the end of the Enlightenment (which had actually started out decently--it was when they abandoned its values of reasoning and questioning just about everything that it went astray).
Well the NK and Chinese armies certainly conducted their side of that war as though they had no God to answer to. They are going to be in for a big surprise at Judgment Day.