one of the reasons why David Horowitz detached himself from the Left came from he and his then-writing-partner Peter Collier writing a book on the Rockefellers
the biggest reason was that he introduced a friend (a lady accountant) to the Black Panthers to do their accounting; they then murdered her (in his opinion, but very likely)
That's right: I forgot that. I was thinking of him as a New-Lefty-type intellectual, not activist. You're right: he withdrew from the New Left and buried himself in theoretical work after that murder. It certainly was the "first doubt."
the clue by four of reality Rich and I were talking about