The article possible uses a false senario. It's been reported that yes, the Nazi/White Supremecy/KKK bunch did spew hateful speech, but were attacked by those opposing their right to do this.
It seems everybody is forgetting the last part of the 1st Amendment. It says the people have the right to assemble PEACEABLY.
https://www.google.com/search?q=the+...&client=safari
The instant you instigate violence, you just violated the basic tenant of the right of assembly. You are the one engaging in an Unconstitutional Act. The Government has the authority to control, by law, all acts that are Unconstitutional.
The instant an ANTIFA member, a BLM member, or an Anarchist throws a bottle, strikes another person, or turns over a car, THEY just violated the Constitution.