As in any war, any side. The British pretty much invented the term concentration camp (Second Boer war). The Americans put many innocent citizens of their own country who just happened to have a japanese ancestry into concentration camps during the war, some of which were fashioned out of horse stables. (The hrses were killed to make room for the people) My point is that all sides in any war will commit atrocities. Using civilians to test out a nuclear bomb on though? That's taking too far too far.