Horowitz was a confidant of Black Panthers leader Huey P. Newton, and provided legal and financial assistance to the black revolutionary organization.
http://en.wikipedia.org/wiki/David_Horowitz
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Horowitz chronicles how his intellectual parents and their friends-- mostly immigrants or first-generation Americans --were drawn to the Communist Party in the 1920's and 1930's; how they passed their idealism and radical beliefs on to their children before becoming disillusioned themselves after Stalin's crimes were revealed in the Khruschev Report in 1956; and how those children-- including himself, Peter Collier, Todd Gitlin, Bob Scheer, Jerry Rubin and many others --established the New Left in the early 1960's, to replace the discredited "Old Left" of their parents' generation and to rehabilitate the Marxist idea.
http://74.125.155.132/search?q=cache:nJbNytn14dQJ:www.amazon.com/Radical-Son-Gen...
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...account of his parents in a communist cell in 1940’s New York...
http://74.125.155.132/search?q=cache:nJbNytn14dQJ:www.amazon.com/Radical-Son-Gen...
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Horowitz was a close friend and associate of Marxist historian Isaac Deutscher. Horowitz wrote a biography of Deutscher in 1971.
http://en.wikipedia.org/wiki/David_Horowitz

Isaac Deutscher (3 April 1907 – 19 August 1967) was a British Marxist historian, journalist and political activist of Polish-Jewish origin. He is best known as a biographer of Leon Trotsky and Joseph Stalin and as a commentator on Soviet affairs. His three-volume biography of Trotsky, in particular, was highly influential among the British New Left.
http://en.wikipedia.org/wiki/Isaac_Deutscher
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