THIS WEEKEND marks the 40th anniversary of the brutal Manson family Tate/LaBianca slayings, so it seemed appropriate to bring back another foundational interview with Peter Levenda, author of the three-volume set Sinister Forces: A Grimoire of American Political Witchcraft. As we read Levenda's work, we realized that Sinister Forces -- and indeed, American history since World War II -- is essentially the six degrees of Charles Manson.