steelblood: I question your assertion that thousands of Americans have been imprisoned for saying things "remotely communist" or even for speaking to a communist. Hogwash. There were some folks who lost their jobs and less than a hundred (maybe a few dozen) directors, writers and actors in Hollywood were blacklisted for a time. But "imprisoned" by the thousands? No.
Yes, when you're in the military your freedom of speech is restricted as are many other things. It's the military, not a democracy.
Yes, the disciplining of the Miami player for a somewhat ambiguous tweet is technically not unconstitutional; it's being done by his employer, not the government. But it is being driven by a PC mob whose views happen to align with the current administration's views. It's not hard to imagine a government stepping in and doing what the mob wants done.