The lock down over COVID introduced me to Heather Cox Richardson. Her history of the Republican Party is a must read if one wants to understand the systemic racism in the United States.
I'm sure there are other historians, I just found her approach more accessible. The other thing is would recommend is studying the 1920's, it seems to be the culmination of all the corruption of American ideals and exploding in October of 1929.
Sadly the thinking of so many has not changed, it's human nature.