"It is not a threat but a fact of history that if an oppressed people's pent-up emotions are not nonviolently released, they will be violently released. So let the Negro march. Let him make pilgrimages to city hall. Let him go on freedom rides. And above all, make an effort to understand why he must do this. For if his frustration and despair are allowed to continue piling up, millions of Negroes will seek solace and security in black-nationalist ideologies. And this, inevitably, would lead to a frightening racial nightmare."