Ambrose Bierce was a Civil War vet, so he's just the kind of guy we want to tell us about what the war was really like. Not surprisingly, Bierce doesn't come off as a huge fan of war. In all of his stories, war is defined by violence, death, and suffering. Though Peyton Farquhar is not a soldier, he too is a casualty of war. Farquhar's war begins in earnest when he decides to support the Confederacy by burning down a bridge. He is subject to military law as soon as he participates in the conflict. The soldiers in "An Occurrence at Owl Creek Bridge" reflect and embody the unforgiving and regimented nature of war.
War is an inescapable force that destroys everything in its path.
Farquhar suffers because he chooses to participate in the war.