...saying that they have no right to march or protest in America?

The fact is that, as scummy as these folks may be, they have the right to assemble, and they obtained the necessary permits in Charlottesville -- backed up by a subsequent court order -- to do just that. They were also defended by the ACLU, by the way.

Rather than allow the RWNJ protest to occur peacefully, however, in which event no one would have ever heard about it, leftist groups -- including communists and Antifa -- descended on the area to counter-protest, which they also had the right to do.

Subsequently, BOTH SIDES engaged in violence and attacks on the other. "The whole Unite the Right thing" was not an example of right-wing violence -- it was an example of violence across the political spectrum.