Lets separate headlines from reality here: Yes this is an unnecessary provocation with loads of emotionally charged elements (and federalizing California's National Guard in this context is certainly concerning for multiple reasons -considering the scale of the protests and violence ) BUT there is no sign that Active Duty military personnel are being deployed to engage civilians (yet).

It would seem most likely that the Marines were called strictly to protect federal buildings, facilities and agents. The problem I see is the latter category. I am personally fine with National Guard being used to protect people and infrastructure when appropriate and when confined to federal facilities, and I'm even fine with the use of military to protect federal facilities... however, the second active duty military engages civilians 'on the streets' we have martial law and that's a whole new can o worms with explosive possibilities for escalation.