It's unconstitutional because labeling antifa as a domestic terrorist organization is antithetical to the first amendment. Doing so would implicate members of antifa solely for joining the group. If someone from antifa broke the law, then of course they can be prosecuted. However, by labeling antifa as a terrorist organization, this opens a Pandora's box that allows people to be prosecuted for joining an ideological group, which is strictly against the first amendment. There's a reason why white nationalists, who are much more dangerous than antifa, are not a terrorist organization. Also, since antifa is an amorphous organization without a clear leader, enforcement of the law would be difficult. Just like how simply being a white nationalist is not and should not be a crime, simply joining antifa should not be a crime either. I'm gonna assume that the stuff about them going to guantanamo or doing hard labor is sarcastic, because doing that would probably be cruel and unjust punishment, also unconstitutional. Antifa has never actually killed anyone, so I don't understand why they would be subjected to worse treatment than actual murderers.
