A counter argument: if we don’t teach kids about the atrocities of war, fascism, and communism, they will grow up ignorant of those things and discover them all over again for themselves, but worse, because we can now slaughter and surveil people much more efficiently than ever before. I’d be in favor of showing “Come and See” by Elem Klimov to school age kids, with peasants burning alive in barns and everything else, because that did actually happen and it absolutely can happen again. In fact I made my son watch it when he was 12.