Most of the protesters here are peaceful, as is usually the case. The biggest demonstration and march yesterday was on the grounds of the state capitol, and that was peaceful. The police, therefore, left these guys alone. Doesn't hurt that though they were in a very visible spot, they were not that close to the convention center.
The problem is the self-described "RNC welcoming committee". Police made several raids before the convention started on these guys, and found things like baseball bats, sharp metal debris, and jugs of urine being stockpiled. They're a nasty group, with a heavy anarchist leaning. Unfortunately, while they haven't done anything truly disgusting, they have been active. And not just going after the police or the conventiongoers, but taking time to smash up a few local businesses, specifically a Macy's, in downtown. There are also spottier reports about them attacking delegates, and hurling bricks off overpasses. Not sure about those, just the rumors that are going around.
This means they are making things harder for everybody else. The police knowing there are anarchists about makes them understandably jumpy (the 90 degree heat probably didn't help). It also means that most people living in the area, even good liberals, are taking a pretty dim view of the protests in general, because what they see are the images of destruction along with crowd dispersal.
Its raining today. Hopefully things will go better.