Richard Milhouse Nixon's greatest gift to Americans remains the thousands of hours of tapes he recorded, the bulk of which is still unheard but lots of which has leaked out just when we're ready to forget him. The latest objects of his curiosity: "All in the Family" and faggotry. Note the sensual manner in which he says "hardhat." Note -- as usual for an avowed fan of Mao -- the unveiled admiration for totalitarian society ("The Russians. Goddamn it, they root'em out...Do you think the Russians allow dope? Hell no!") and