It’s really long for the internet, but still a good read on who the “other” really is in America.
So what makes an outgroup? Proximity plus small differences. If you want to know who someone in former Yugoslavia hates, don’t look at the Indonesians or the Zulus or the Tibetans or anyone else distant and exotic. Find the Yugoslavian ethnicity that lives closely intermingled with them and is most conspicuously similar to them, and chances are you’ll find the one who they have eight hundred years of seething hatred toward.