In the poem "I, Too, Sing America" by Langston Hughes, the speaker talks of being discriminated against because of his skin color. The speaker talks of a dream he has in which he will not be judged for his race.
In the poem, the speaker states that he is also an American, but that the country is ashamed of him. During the period in which it was written, African-Americans were treated as second-class citizens and were subjected to Jim Crow laws.
By continuing to state that he is also an American, the speaker is letting the audience know that he is equal to others and should be given the same liberties as white Americans.