I think that's a reasonable approach, and there has been criticism of police (on "many sides") that police in Charlottesville didn't do enough to protect peaceful protestors. In this case, it seems that all of the serious injuries were inflicted by Neo-Nazis on peaceful counter-protesters, but there have been cases where antifa has inflicted injury, perhaps even without provocation.

Charlottesville police seemed underprepared for this event, in general. Many, many, reports from a wide variety of people noted a complete lack of police presence in a number of situations where violence occurred, or that police were present but merely observed violence taking place.

This leads to a lot of mistrust of police, and also makes it harder for protesters who might like to remain non-violent to do so. If you see someone being beaten up by Nazis and police aren't stopping it, the only decent thing for an able-bodied person to do is to try to stop it.

> Charlottesville police seemed underprepared for this event, in general.

Core problem seems to be that lots of the Nazis (and to a lesser extent, some of the protesters) were heavily armed. It's easy for police to break up a protest where no one is armed, but they sure as hell won't mace a group of heavily armed people, no matter if Nazi, Antifa or whatever.