I think you are half right. However, it will not be the fascists or even the Alt-Right that will destroy the anti-fascists (Anti-Fa). As happened before, the normal people, those who abhor violence, the majority, will see the violent extremists on both sides for the self-absorbed narcissists they are and crush them. However, since it is the deep state and the elite who control the MSM and are not so secretly supporting Anti-fa by painting anyone who disagrees with them as "fascists", that resistance from the overwhelming majority could turn out to be a revolution.