This mentor has a name. I wonder why the Washington Post didn't mention it? Barry did in his book. He called him "Frank". Just "Frank". The Commie mentor's full name is Frank Marshall Davis.
More info about Davis here. So what is it that the Post disputes? Was Davis not Barry's mentor? Was he not a Communist? Why don't they say?
America’s Survival Inc.: http://www.usasurvival.org/