The best aspect of Chicago as represented by Sandburg in his poem is its strength and vibrancy. He portrays the city as "Proud to be alive and coarse and strong and cunning", "laughing with the stormy, husky, brawling laughter of youth". Chicago is an earthy place, "a tall bold slugger set vivid against the little soft cities". It is not for the faint of heart, but it is the wave of the future. "Building, breaking, rebuilding", "piling job on job", Chicago will carry the people on its "Big Shoulders"; "under (its) wrist is the pulse, and under (its) ribs the heart of the people".
Sandburg admits that there are bad aspects of the city. He acknowledges that it is "wicked", pointing out the "painted women under the gas lamps luring the farm boys" as an example. He also admits that the city is "crooked", saying that he has "seen the gunman kill and go free to kill again". Sandburg also says that Chicago can be "brutal", a fact that can be seen "on the faces of women and children...mark(ed with) wanton hunger". Still, despite these realities, it is obvious that the poet has a deep love for the city of which he writes.
The worst comes in the form of judgments passed on the city. Sandburg refers to these judgments, listing them as someone speaking them out loud: "They tell me you are wicked...crooked...brutal." He admits that "they" are in fact correct; he doesn't deny it. Chicago is wicked, crooked and brutal. He describes those traits in more detail:
"painted women under the gas lamps luring the farm boys...gunman kill to go free and kill again...the marks of wanton hunger" on the "faces of women and children."
So, those traits are the worst of the city. However, despite this, Sandburg also describes much about the city that he loves. The best sides of it is its
"lifted head singing/so proud to be alive and coarse and strong and cunning."
He emphasizes that even in the dire, poverty-stricken misery of the city that people are "strong", "fierce", "laughing", "bragging", and happy to be alive. He emphasizes the strength of the working class of Chicago, and how they are proud to be who they are, and happy in their station, full of vivacity and life. So, Chicago is a lively, strong, intense city, and those are its best traits, mixed right in there with its worst.