Edited sentence: Communism—as an indigenous force, as yet another manifestation of diaspora politics, or as an instrument of Soviet policy—achieved astonishing influence not in its own right, much less on its own behalf, but as an agent for poisoning American politics.Government secrecy, as the commission was discovering, played a large role in all this.National politics and national security are always to some extent interrelated, but in the years of the Truman presidency the relationship became problematic.The effects were felt for a generation or more; the reverberations are felt even today, after the collapse of the Soviet Union.There were no Communists in Kansas City politics where he came from.Truman has been criticized for putting domestic politics above American security.Trust leeched out of the political system, loyalties waned, betrayal became common