For a minor masterpiece of evasion, check out Maurice Isserman's recent review in the New York Times Book Review of John Earl Haynes and Harvey Klehr's new book Venona: Decoding Soviet Espionage in America. Klehr and Haynes have spent much of the decade doing yeoman work, mining the archives of the American Communist party and the decrypted Soviet telegraph traffic from the 1940s known as "Venona." Both of these sources have demonstrated beyond cavil that large numbers of American Communists spied for Moscow before, during, and after World War II.
This is a bit inconvenient for revisionist historians like Isserman, whose best known work, "Which Side Were You On?", is a history of heroic American Communists during World War II that you might say was rendered obsolete by the Venona intercepts. Isserman admits that "facts are stubborn things," and that, yes, his previous work was somewhat akin to staging Hamlet without the prince, but no matter. "Historians," he intones, "need to ask other kinds of questions, the kinds that would not necessarily be of interest to prosecuting attorneys." Words like "treason" get in the way of such a discussion, because they "make it difficult to draw the distinctions necessary for exploring historical complexities."
Isserman prefers to say that some American Communists had "a romance of the clandestine." Oh, and he wants you to know, that there's an upside to the story: "Of the approximately 50,000 party members in those years, 49,700 were not involved in spying." Right. They were just incurable romantics who sided with Stalin.