WASP doesn’t appear much these days but it used to name the American privileged group, White Anglo-Saxon Protestants. That expanded easily to include northern Europeans, but not Irish because they were Catholic. Italians also did not qualify as white Americans. If they were Sicilian they could be tarred with Mafia identity. At least 50 were lynched in America around 1900. (Northern Italians don’t like Sicilians either.)
Germans, despite their big presence in Pennsylvania, were justifiably hated during two world wars. That has disappeared, but their hatred of Jewish people has a long European history. Some Americans adopted that too. Countries further east could not be accepted – there were jokes about Poles. Russians seem to have been neglected in the history of American bigotry though as communists they could deserve hatred. People of Spanish heritage or language are not candidates for “whiteness” no matter how light-skinned or “Caucasian” they are.
Given these discriminations it is clear that African, Arabic, and Asian peoples could not be white, “really American.” With Africans the repudiation is most intense because of slavery. Throughout history people have enslaved captured enemies, but it was made more intense by skin color. This prejudice has been the cruelest in America.
All this reprehensible thinking has appeared in people who supposedly affirm the equality of all human beings. Of course that language is dismissed as rhetoric, hardly ever applied to daily life and local relationships. Americans, like all human beings, simply have wanted to hate other people who look different, don’t speak English, have other religions ...
All this is generalization, of course. If you do not agree with your compatriots in the history of prejudice, you might hope that this is not true of most Americans today. But this is what we look like to many in the world and certainly what our ancestors have affirmed or tolerated.
The only remedy is mixing. Clubs, neighborhoods, politics, and families can include all kinds of folk. The more you know, enjoy and work with others, your own identity changes to include them as “us.” Those that reject inclusion today will eventually die and their offspring will grow up in less hate-filled communities.