Generally in that era as well as still recently, most soldiers and nations tend to dehumanise what they saw as enemies or just make excuses for who they hate. But it wasn't all like that though. There's probably countless undocumented stories where people actually helped others as people. Like the time when a Japanese destroyer saved U.S. sailors from a sinking ship, Germans hiding Jewish people from Nazis, British soldiers stopping U.S. soldiers from killing African Americans, the U.S. stopping the French from committing a genocide in Algeria, etc.
Every nation hated someone for something, but there are a lot more people who realize the pain and suffering but goes unspoken.