I don't know about communists, but I do know of some Anarchists, and this article I found that talks about it mentions "a large number of [people]." There were perhaps communists with them, it gives that impression; I'd be surprised if they were all anarchists.

Palmer and his assistant, John Edgar Hoover, found no evidence of a proposed revolution but large number of these suspects were held without trial for a long time. The vast majority were eventually released but Emma Goldman, Alexander Berkman, Mollie Steimer, and 245 other people, were deported to Russia.

http://www.spartacus.schoolnet.co.uk/USAcommunist.htm

Like someone in another comment mentioned, there's the modern day issues (Guantanamo), but I don't think it should matter much which country it happens in - the point is, our government isn't a white knight either. In the declaration of independence the words read that all men have such unalienable rights by God (not because of where they are born), and so it is hypocritical for the same political justification and claim of truth to alienate these rights when it is elsewhere.

That said, I am arguing for things that I don't think matter - I do this for clarity. I guess there's also no reason to go into why it doesn't matter here.