From my perspective the two authors describe american identity in different ways. While Walt Whitman uses the working class as the main staring people in his poem, Hughes fights for the recognition and rights of African-American people.
Whitman uses the similarities that binds all of his characters as they are part of the working class. Whitman celebrates in this poem the laborer, whom he views as truly embodying the American. (These are the people, part of the society, often overlooked by poets.) Moreover, the song he hears is them at work – the sound of the carpenter sawing wood or the mason laying his stone. A really interesting, and progressive, part of this poem comes in line 8, when Whitman decides to include women at their domestic labor in his catalogue. The work that women do as mothers, as homemakers, as “the girl sewing or washing” contributes as much to America as the male labor performed outside of the home. In this way, Whitman’s vision of America is inclusive regarding gender.
For Whitman, America is made up of individuals but who form this nation as community. (Your textbook identifies this as the American ideal of e pluribus unum – “Out of many, one.”) To give a bit of historical context, Whitman publishes this poem in 1860, three years before the outbreak of the Civil War. So when Whitman writes this poem stressing American unity, he is witnessing his country dividing along political lines. Even today, we might question the accuracy of Whitman’s vision of America as harmonious – are there those whose voices are not included in the song of America?
On the other hand, Hughes in the opening line of the poem (“I, too, sing America”) is a direct response to Whitman’s “I Hear America Singing.” Hughes’ word-choice is important here. The first word of the poem, “I,” suggests an urgency to assert his identity. The “I” here is not just Hughes but is more general – the “I” is that of the African-American. Hughes’ use of “too” creates a sense that his song, his voice, has been overlooked and not listened to in the carol of America. The black American experience, that defined by slavery, violence, dehumanization, segregation, is a part of our national identity and history, albeit one that is hard to accept. In the opening to his poem, Hughes rightfully demands recognition for this part of the American song, that has been mostly demeaned and neglected.
From my perspective, a characteristic that we share as Americans is the need to break away from the old, the rigid, the conventional.