"Even" US army forces were ordered to commit atrocities (for the usefulness of terror ot for the quick fix/shortcut of it), but some units did them in their own (that command may or may not have found out later about). It's just that war is chaos, & fog of war very real and a tool. The logistics of war are insane & at every level there are just individual people prone to people things.

Propaganda paints a picture for you and the tool to flight it is knowledge.