What is the exposition in the short story "Soldier's Home" by Ernest Hemingway?

The exposition is a part of the plot of a story which includes the setting, characters, and the basic situation. Hemingway's short story "Soldier's Home" is set in the Oklahoma town which is the home of the main character Harold Krebs. Other places which are mentioned in the story include the Methodist college which Krebs attended, places in Europe which Krebs encountered as a Marine fighting in World War I, and Kansas City, where he claims he will go to find a job at the end of the story. Krebs is the main character. He seems to be suffering from trauma and stress caused by the war because he tends to be apathetic and somewhat anti-social.
Other characters in the story include Krebs's devoutly religious mother, his father (who is prominent in the story despite the fact that he actually never appears but is often referred to) and his sister Helen. The basic situation is that Krebs has just returned from the war. The third person narrator states that Krebs fought in some of the most important battles of the war and also describes a photograph, taken in Germany, of Krebs, another soldier and two women. It seems to suggest that Krebs's military experience was unheroic considering that the German girls were "not beautiful" and the Rhine River, often described in the mythic tales of Germany, "does not show in the picture." As with much of his fiction, Hemingway never explicitly refers to important details which could be included in the exposition, especially Krebs's direct experience in combat. These details might go far in explaining Krebs's apparent inability to reintegrate into society.