The latest sense of this I've observed most recently comes from a 70-year-old white, Irish-German Chicagoan who had come to California at age 10. At various times, he exhibited apologist views for Germany in World War II. He may have voted against Trump, but he's constantly trying to excuse the ignorance of "the Base." And always -- always -- I hear this story about how blacks in Chicago destroyed his neighborhood. This was also a theme of others I knew in the same So. Cal milieu from the Midwest, whining about how blacks "destroyed" their neighborhood (housing values) after housing discrimination became illegal in the '60s and '70s.
Those neighborhoods were always vulnerable to decline, with or without a black presence. But it's really the same argument you could find from white college-aspirants who didn't get accepted at this or that university, blaming their troubles solely on affirmative-action and quotas.
One could argue this is similar to an attitude we perceive among climate change deniers. They don't want to be responsible for the 200+ years of accumulated CO2 emissions. Why should they bear the inconvenience of a reduced life-style because a bunch of dead people already poisoned the planet?
And so, why should we hardworking working-class white people suffer setbacks because blacks were mistreated for 400 years? Most of the setbacks are imaginary. You can be unhappy about a lot of things, but it always helps to have an easily-identifiable scapegoat.
Besides -- "we're white." "America was a great place -- once -- for 'white people'."
Ultimately, I see this as a problem of diminishing-majority racial identity and the dilemma of choosing sides. Frustrated white people need to consider rejoining the Human Race and rejecting their sense of privilege.