In theory, Guantanamo Bay detains foreign nationals who did a lot more than just say "oh one day the world will be better off as a theocracy". Planning to overthrow US government to build either communism or theocracy is illegal and I am Ok with that. Speech is something not mandatory for me to hear and something I am not forced to follow.
In practice, I am sure there are many abuses and lack of due process to establish that each detainee is in fact a terrorist. But comparing that to extermination of millions by Stalin or Ughur reeducation camps in China is ridiculous. It's a small number of individuals who slipped through the cracks, and any system has cracks.
