"White people have never been formally denied equality before the law except for white women who gained the legal right to vote in 1919."

Your badly misinformed there. The Irish were abused horribly, just to name one group of immigrants, as were the Mormons. American history is littered with discrimination against various groups, and it wasn’t just due to color of skin. 

https://www.history.com/news/when-america-despised-the-irish-the-19th-centurys-refugee-crisis