In a novel of this type the conflict usually involves two opposing military powers. The characters, such as Frederic Henry and Catherine Barkley, are little people caught up in a gigantic conflict. Italy was on the side of Britain, France and America in World War I, although it was on the side of Germany in World War II. There doesn't necessarily have to be a conflict between the characters themselves. In fact, too much conflict might be confusing. The story is about how their lives are affected by something much bigger than they are. The same is true even of the great Leo Tolstoy's War and Peace. The conflict there is between France and Russia. Napoleon Bonaparte is the protagonist. In Gone with the Wind the conflict is between the North and the South. In Ambrose Bierce's short story "An Occurrence at Owl Creek Bridge" the conflict is also between the Union and the Confederacy. And in Homer's Iliad the conflict is between the Greece and Troy. Sometimes critics look for a conflict in a story like A Farewell to Arms with a microscope, when an enormous conflict is staring them in the face. Wars usually exist because of the machinations of selfish, ambitious individuals. Such conflicts are usually about money. We are all affected by conflicts between powers much greater than ourselves.