Trump doesn't reign, he barely has control of the executive branch of government over which he has direct authority. He is opposed by his own party, congress, and big business. There is no collusion of power behind Trump like there is behind Putin. They are both seen as strong men but only one is really a strong man.
Second, classifying ANTIFA as a terrorist organization is nothing like Russia cracking down on Nazis. In the US you have free speech even if the government believes you are a terrorist organization. Now if the left wing get's their way and starts imposing hate speech laws, then ANTIFA needs to watch out because then they will be silenced by the government.
Finally, there is a deep respect for protesting in the US but not for people who do it hiding behind masks. Ghandi didn't wear a mask, Malcom X didn't wear a mask, the kids at Kent State that were shot by the police didn't wear masks. A mask indicates you are there to do harm. Sometimes harm is warranted, but we respect protesters who actually practice Civil Disobedience, part of which is owning up to what you did.
My only point here is that I believe Antifa would get more support from the American people if they could convince the 10-20% of members that show up dressed in black and wearing masks to just dress down and lose the goon squad apparel.