King was wrong to look to the State for economic equality - welfarism. He was right to look to the State to overturn the State's own inequitable laws.
What does slavery have to do with anything? There was no easy solution to slavery, but I don't see how an internal war is one of them. No other civilized Western nation in the world ended slavery by mass bloodshed. As far as Jim Crow is concerned, those were State laws and legislation that created that system. Individuals have every right to ignore, fight, protest, whatever against injustice from the State.