Yes and no. I think we have all agreed that the individual acts of the officer are probably a problem, but the overall system seems to be working OK. The guy was fired and charged with murder. Not sure what else you want them to do at this point.
Here's the funny thing about the violent protests you like- people see the craziness in Baltimore, and maybe rather than thinking "wow, those poor people are really upset, we have to do something to help them" there are probably just as many who think "OMG, those people are animals, we really need to support the cops who are putting themselves at risk dealing with those thugs."
Which in turn probably shapes perceptions of how justified the police are when they have to resort to force. A lot of folks are likely to decide it's a valuable thin blue line, or at worst just the lesser of two evils.
I don't see any rah-rah-ing, just don't share your dystopian ideals. I would not want someone as a neighbor who refused to help in a crisis, would not engage with public services, and constantly denigrated the people who are doing a hard and dangerous job for crap wages. People need to obey the rules and no one is above the law so if the guy in SC is guilty let's see if he gets punished. But I don't see it as a reason to gleefully undermine the guys who are doing a good job.You can rah rah and cheer for America all you want - I think it's great that someone is still doing it, in a way - but this incident in South Carolina is not isolated and unusual.