"The principal feature of antifa groups is their use of direct action, with conflicts occurring both online and in real life. They engage in varied protest tactics, which include digital activism, property damage, physical violence, and harassment against those whom they identify as fascist, racist, or on the far-right.
Activists involved in the movement tend to be anti-capitalists and subscribe to a range of ideologies, typically on the left. They include anarchists, socialists and communists along with some liberals and social democrats. Their stated focus is on fighting far-right and white supremacist ideologies directly, rather than through electoral means. Wiki on Antifa
I spent time this AM seeking the legal authorities needed to outlaw Antifa as the violent, seditious pastiche of anti-American lefty groups that it is.
I found none. The US AG used to have a list of subversive Groups; The Communist Party, Nazi Party, The Black Dragon Society, The Knights of the White Camellia, etc. This was a useful list. It could be used to exclude Dragoneers, etc. from federal employment, personnel security clearances for federal information and it made surveillance of such people by the FBI automatically authorized.
But, alas, Nixon abolished the list. Try to come to terms with that, lefties.
At present there does not seem to be a suitable tool in the equipment of DHS or the FBI,
That, actually, is a good thing. Some future administration would love to shut down opposition groups if it had the legal tools.
Go meet them in the streets! Go greet them en masse. They think they will like that. See if they do pl