Unfortunately too small to read, but I remember the quote now.

First, I must confess that over the past few years I have been gravely disappointed with the white moderate. I have almost reached the regrettable conclusion that the Negro’s great stumbling block in his stride toward freedom is not the White Citizen’s Council-er or the Ku Klux Klanner, but the white moderate, who is more devoted to “order” than to justice; who prefers a negative peace which is the absence of tension to a positive peace which is the presence of justice; who constantly says: “I agree with you in the goal you seek, but I cannot agree with your methods of direct action”; who paternalistically believes he can set the timetable for another man’s freedom; who lives by a mythical concept of time and who constantly advises the Negro to wait for a “more convenient season.” Shallow understanding from people of good will is more frustrating than absolute misunderstanding from people of ill will. Lukewarm acceptance is much more bewildering than outright rejection.

And King was not unsympathetic to the rioters.

And I must say tonight that a riot is the language of the unheard. And what is it America has failed to hear? It has failed to hear that the plight of the negro poor has worsened over the last twelve or fifteen years. It has failed to hear that the promises of freedom and justice have not been met. And it has failed to hear that large segments of white society are more concerned about tranquility and the status quo than about justice and humanity.

He also didn't wholly disagree with Malcolm X.

While we did not always see eye to eye on methods to solve the race problem, I always had a deep affection for Malcolm and felt that he had a great ability to put his finger on the existence and root of the problem.