As he does in The Great Gatsby, Fitzgerald here alludes to a darker side of the Roaring 1920s. Both here and the novel, the term “restlessness” is key. In the opening chapter of Gatsby, Nick describes introduces himself with the term.
I enjoyed the counter-raid so thoroughly that I came back restless. Instead of being the warm centre of the world, the Middle West now seemed like the ragged edge of the universe — so I decided to go East and learn the bond business.
Tom and Gatsby himself are also described with this quality of “restless.” Both at the beginning and end of the novel, Tom’s eyes are described as “restless.” And Gatsby too also has an underlying sense of “restless” despite his suave facade:
He was balancing himself on the dashboard of his car with that resourcefulness of movement that is so peculiarly American—that comes, I suppose, with the absence of lifting work or rigid sitting in youth and, even more, with the formless grace of our nervous, sporadic games. This quality was continually breaking through his punctilious manner in the shape of restlessness. He was never quite still; there was always a tapping foot somewhere or the impatient opening and closing of a hand. (Chapter IV)