"Frightened people will do terrible things." My mother lived through the Hunger Winter in the Netherlands, and she told me this once. Yes, when people are frightened they often lose their ability to empathize.

Additionally, we have made some progress in empathy between WWII (when black people were kept in black regiments and weren't allowed to use certain places of business or sit in the front of the bus, and let's not even talk about attitudes to gays) and now.