Letter from Birmingham Jail. Who was the intended audience?

On the surface, “Letter from Birmingham Jail” is intended for the Birmingham clergymen who published an open letter criticizing the actions of Dr. King and the SCLC. And yet little by little, it becomes clear that Dr. King intends this statement for a much larger audience. Based on the arguments he makes and the stipulations he assumes, it is possible to construct the audience he means to be affected by this letter: a moderate, white, generally moral but conflicted group. He is clearly addressing people who represent the power class, but assumes in several arguments that they support the ideals of justice, at least on the surface. More specifically, he assumes they accept the validity of Christian morality. And yet his harsh tone is much more universalist than simply the criticism of the clergymen would support. In attacking moderation, he addresses himself to parties as high-ranking as the Kennedys to as everyday as students and churchgoers who are witnessing the changes of the civil rights era without admitting their own moral responsibility to support it as a quest for positive change.