When I was a graduate student at Columbia University's Russian Institute, there was a great debate: Was the communist Soviet Union an organic Russian development or was it largely a cancer imposed on it? Those who held the organic view argued that the change from czar to commissar was only one of degree. Both were tyrannies, the latter more tyrannical than the former. I agreed with the second view, that communism was something radically new, not a logical, let alone inevitable, Russian path. The czars were autocrats, not genocidal totalitarians. I have to admit that in recent years, I...