Impy, communism is intrinsically evil and people who do commie organizing are engaged in criminal behavior. So, yes, it is proper to criminalize this type of politics.
Same thing with the Nazis. They are criminals. Organized crime. (Just my viewpoint.)
I suppose you’ve seen the video here
http://freemarketcircle.blogspot.com/2011/07/jack-webb-schools-obama-on-america.html