I think that McCarthy did enormous damage to the anti-Communist movement in America. Not because he was wrong, but because he was a drunk, and he absolutely lied and exaggerated.... When McCarthy started spouting numbers that constantly changed, when he claimed to have a list that he could never produce, he created the environment and context for the entire process to be characterized as a "witch hunt." DING DING DING -- We have a winner.
Frankly, I would not be surprised in the least if some dusty old document turns up in the KGB archives describing how the whole thing was set up to discredit legitimate and rational investigations into Soviet infiltration.