If you want to see how thoroughly our government/CIA was penetrated, check out the following link. McCarthy was right, Alger Hiss was just the tip of the iceberg.
http://www.freerepublic.com/focus/f-chat/1224848/posts
What a crock. He mentions Ames, who offered himself up to the Soviets due to severe financial and alcohol problems and then makes the unprovable allegation that the CIA is full of moles. No one can say for sure that there aren't any other moles, but he has absolutely no evidence the Agency is full of moles. Any intelligence organization that employs thousands of people is going to occasionally have people who for one reason or another sell or give away secrets. None of the espionage cases in the last 20 years were due to an allegiance to Communism, but in most cases a result of overblown ego, money problems, or alcoholism. In the 30's and 40's they were almost universally the result of a belief in communism. There is a big difference.