<Your post, for instance, chides them for remembering that slavery is a part of their past, their fairly recent past.

Recent? Bullshit. There haven't been any slaves in this country since Lincoln. Again, get over it. The current social engineering and welfare state schemes have done much worse to blacks in modern times than any vestiges of slavery left over from 140 years ago. Check any statistics you want.

As far as free association of people are concerned, you are right on the face of it. Ideally, anyone should be able to associate with anyone they want, and exclude anyone they want.

The flaming hypocrisy shows up when the shoe is on the other foot. Try imagining a meeting of white people who ask all the black people to leave because they make them "uncomfortable." Right.

Half the effort of liberals in America is dedicated to taking groups who want to exclude certain people and forcing them at gunpoint to accept whoever the liberals think should be allowed.