There's no correlation here. McCarthyism was the attempts by the government to interfere with the views and jobs of public figures. What's happening now is that the common Joes and Janes of America are doing exactly what they've been told to do for years... they are voting with their pocketbooks. These celebrities are upset because they do not want to accept the fact that most Americans, despite what the media says, do not support the same positions that they are taking.
We are free to express ourselves and our beliefs, but we are not free to not be held accountable for what \we say or the stands we take. I think this celebrity whining is just another example of how shallow and phony these clowns are. They are more than happy to take their perceived high road when there is no fear of retribution or chance of penalty. Martin Sheen loves getting videotaped while he's being arrested at some demonstration, but he knows that he's going to be released in an hour and will suffer no real penalty. If he faced going to prison and doing hard time like other activists around the world have you can bet you wouldn't be seeing Mr. Sheen, or Mr. Sharpton, or any of these other "activists" doing anything that might get them arrested.
Having moral conviction means being willing to place your best interests at risk for something you believe in. Any wiener can say that they are a rebel when there is nothing to lose.