Where there communists in Hollywood or in government structures of a purely philosophical nature? Undoubtedly. Where there communists in either who were actively engaged in intelligence-gathering and espionage for the Soviet Union or one of its satellite republics? Very probably. The problem is that Joe McCarthy, in trying to remove the threat of the latter, ended up attacking both, and circuмvented the law to do it.
The regrettable truth, and it's one that forever prevents me from being American in anything other than name, is that the Constitution of the United States permits total intellectual freedom, of thought and word. No matter how offensive it might be, the freedom of speech, and hence the freedom of thought, cannot lawfully be abridged in any particular by sitting government. Oh, there are state or local ordinances, blue laws and the like, that govern vague notions of public decency, but those just go to show you that the entire notion of democracy is a lie and a swindle. By our own permissions of "exceptions" to the law, which we happen to personally agree with, we have over the course of the 237 intervening years hollowed out the fruitful notion of governance through dispassionate application of law, and left it to rot. It lays bear the truth that democracy is simply tyranny by creeping degrees and that we have been the authors of the very oppression under which we chafe. To look at the United States and communist Russia as being opposites is to believe that your right and lefts arms are not both attached to your body; the two are both appendages to the same body of Godless, anti-Incarnation naturalism, that seek, futilely, civil order through other than Jesus Christ.
Under the notion of liberty in the US Constitution, false and damnable though it is, being a communist is not against the law. However, being tried in a court of congressman, and in the court public opinion, rather than in a court of one's peers, usually without even the Constitutional requirement of having the charges known, is illegal. If they had evidence that this person or that person were a communist infiltrator, that should have tried them formally in a court of their peers, or else surveilled them until they did. That said, I don't completely blame Joe McCarthy for the events of the Red Scare any more than I completely blame Caiphas for the Crucifixion. The whole people, in both cases, bear the stain of guilt.
And should it be any wonder, to any of us, that so much time and effort is be expended to conjure the ghost of McCarthy, washed clean with the baptism of sentimentalism and equivocation, for the modern day? A day in which our every communication is monitored, every book borrowed or word applauded dumped into Bayesian metrics to find the Goats among the Sheep that don't toe the line and don't believe, with a Baptist's fevered certainty of Rapture, that the elected swine have our best interests at heart? They want us to want the witch-hunt, and they use neoconservative shills like Beck and Coulter to put the spout the same old catch-22: "If you've done nothing wrong, you've got nothing to worry about." Believe that at your own risk. All godless governments seek to criminalize their citizens; the only way to oppress them with impunity is to make each and every one one of them believe that they're guilty of something. Democracy is, after all, tyranny by creeping degrees, and your crime against the Devil that some of you seem to be defending is just a matter of timing and expediency.