The burning and looting seems to happen when people have their backs pushed up against a wall. Just like the LA Riots happened when the pigs that beat the fuck out of Rodney got off free with nothing.
Sure myself as a white guy living in a really nice home with plenty of money makes me completely isolated from the concerns of most of these looters.
As for the Portlanders doing what they do, most of them are educated middle class, they want government authority to shrink, it's the same thing I want, but I have no access to activism of that sort. Oregon is unique in their activist culture where you have University theory mixed with plenty of time on their hands to get involved in a setting of natural paradise. These people feel they have something worth fighting for, much of the interior of this country doesn't have much more than some bleak future of a life spent manufacturing dog food in a location of flat plains with few trees, death can't come fast enough for these midwestern grunts.