I don't need to believe it is true. However, a substantial chunk of the US population has European ancestry. I never met the immigrant generation, but certainly

I don't need to believe it is true. However, a substantial chunk of the US population has European ancestry. I never met the immigrant generation, but certainly three, I think five, of my great-grandparents came from Europe. One grandfather grew up speaking Platt-Deutsch along with English. Something--many things--motivated these ancestors to move. This may be in the back of our minds. There is also the matter of a certain inborn prejudice in favor of one's country. If you're not in a really awful setting, you probably think well enough of it, and imagine that others would.