What are the important things Martin Luther King wants his audience to know in his "I Have a Dream" speech?

King's
main message in the "I Have A Dream" speech is that African Americans have not yet
received the rights to which they, as Americans, are entitled. He essentially summarizes this
point early in the speech when he says:

One hundred years
later [after the Emancipation Proclamation] the life of the Negro is still sadly crippled by the
manacles of segregation and the chains of discrimination. One hundred years later, the Negro
lives on a lonely island of poverty in the midst of a vast ocean of material prosperity. One
hundred years later, the Negro is still languishing in the corners of American society and finds
himself an exile in his own land. So we have come here today to dramatize an appalling
condition.

King emphasizes that this "appalling
condition" is made worse by the fact that the United States promised its people certain
rights and liberties. In the United States, all men are supposedly equal. King dramatizes this
point by referring to the Declaration of Independence and the Constitution as a "promissory
note" on which the United States has thus far defaulted. In other words, the nation had
failed to live up to its promises, and King and the marchers were gathered in Washington to push
them to do so. This was more or less the extent of King's prepared remarks. The most famous
portion of the speech, though, was extemporaneous, occasioned by Mahalia Jackson's famous
entreaty to King to "tell them about your dream." This was really as statement of
King's vision for the future, one in which the color of one's skin was no longer a reason for
discrimination, and in which racism, systemic and otherwise, was purged from
society.

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