I'm opposed to protests blocking major thoroughfares 100%. If you want me to have empathy for your cause don't act in a borderline anarchist manner, flaunting the law, punishing innocent people by disrupting their lives. Not to mention the reallocation of emergency service personal AND as is typically seen, the disruption of their fastest routes to real emergencies.
Haul the protesters all away, ticket them and call it good. If they resist, even passively, charge them with resisting arrest, trespassing etc.
I'm opposed to running over or shooting non-violent protesters.