Dramatically, this chapter provides the novel's second major turning point, as Lieutenant Henry's war wound will remove him from action and thus enable his affair with Catherine Barkley to grow into love.
Thematically, Hemingway uses the discussion among the drivers in the dugout to articulate his beliefs on war, or at least his beliefs on World War I. (The writer was an ardent supporter of the Republican, or anti-Fascist, side in the Spanish Civil War, subject of his later novel For Whom the Bell Tolls.) Since Henry is relatively inexperienced and therefore naïve at this point in the novel, it is Passini who puts these ideas into words: that nothing is worse than war, that war makes men go crazy, that those who fear their superiors are responsible for war. "Everybody hates this war," Passini says. Perhaps Passini plants the idea of a separate peace in Henry's head when he states, "One side must stop fighting. Why don't we stop fighting? If they come down into Italy they will get tired and go away."
Henry, by contrast, is still talking about bravery (though, significantly, he does admit after the first shelling to being scared). In a bit of foreshadowing that will prove ironic, he argues against giving up: "It would only be worse if we stopped fighting." He says defeat is worse than war itself.
