>zero widespread cultural support. Violence is not glorified by any prominent voices on the left.
This is just not true.[1] Even in our tech community it's pretty commonplace to see 'it's okay to punch a nazi' is a well supported position.[2]
[1] https://heatst.com/culture-wars/prominent-leftists-celebrate... [2] http://reason.com/blog/2017/02/15/now-its-okay-to-punch-nazi...