white supremacy is the uniting factor, when the actual uniting factor is ethnic conflict.

IMO: I would disagree; it still goes back to white supremacy. We can see it in Palestine, where the zionists share the same religion with some Palestinians, but they do not share the same skin color, so they are treated as second-class citizens even in Israel.

An ethnicity or ethnic group is a group of people who identify with each other on the basis of perceived shared attributes that distinguish them from other groups. Those attributes can include a common nation of origin, or common sets of ancestry, traditions, language, history, society, religion, or social treatment.

White supremacy is the belief that white people are superior to those of other races and thus should dominate them. The belief favors the maintenance and defense of any power and privilege held by white people. White supremacy has roots in the now-discredited doctrine of scientific racism and was a key justification for European colonialism.