Noting that Antifa is mostly getting a pass is a fair point. They have been violent before — for example, in Berkeley earlier this year— and they came to Charlottesville planning to be violent.

However, I don’t think you’ve correctly classified them as pro-Soviet. As the name suggests, they are predominantly anti-fascist, which they define to include Nazis, white supremacists, and other far right extremists. (Though they probably draw the line separating far right from right a little closer to the center than most).

Their distinguishing characteristic is advocacy of force against those they’ve identified as fascist, even if their targets are not using force at the moment.