It seems to be a feature of Leftists throughout history that they begin at some point to execute one another. One faction warring with another faction, etc.
As J. Peterson so astutely observed; while contemporary right wing politics has clear lines of demarcation on what they will not accept on their end of the spectrum, e.g. Neo-Naziism, the left wing has no such clear cut limits on themselves. They'll accept any extreme including loss of liberty and murder in pursuit of their "worker's paradise."