I'm, sorry but in order for someone to answer, we need more information.
Answer:
Anna Quindlen considers that America is "an improbable idea", because it was created with the idea of equality between men, but it is impossible to maintain this equality within so much diversity.
Explanation:
To support this idea Quindlen shows that America is a mixed-race nation, very diverse and without a cultural and racial unity in its territory. This stimulates the social difference between people, completely removing the issue of equality, when a group of individuals considers themselves superior to other groups because of their cultural differences and differences in values and customs.
The figurative language in the poem help set a dark and stormy mood, and seems to represent the cycle of death. The term "Old age should burn and rage at close of day" supports that. The exciting terms " Old age should burn and rage at close of day may represent those fighting to stay alive and not be forgotten. This is the best I could figure out from the poem. Hope this helps! Comment if you think answer is dumb lols.