Additional insight for this, from my perspective as support ops for protesters in Portland.

Bad actors from eastern Oregon, a heavily red and still pretty racist part of the state, would come into otherwise peaceful protests and cause property damage so police would be able to use greater force. It's a very effective way to get a protest re-labeled as a riot.

Remember, Oregon banned black people as a way of dealing with the Civil War. [1]. Portland is a liberal island in a sea of of red, hence why it's become such a friction point.

[1] https://en.wikipedia.org/wiki/Oregon_black_exclusion_laws