Or escalate to a civil war. Or embolden the populace that then quickly oust the current regime like in Ukraine. It should be possible to box in a street where damage is being done with 19.000 police officers on location. Or how they usually do it here in the Netherlands, with dozens of undercover officers among the protesters. As soon as they see persons causing damage they follow, position other officers, and apprehend when the opportunity presents itself. And with new things like drones that track every moving object the size of a football and bigger in a five square mile area it should be easier today then it was before.