Epigraphs are like little appetizers to the great main dish of a story. They illuminate important aspects of the story, and they get us headed in the right direction.
What stays with you latest and deepest? of curious panics,
Of hard-fought engagement or sieges tremendous what deepest remains?
-Walt Whitman, "The Wound Dresser"
What's up with the epigraph?
"The Wound Dresser" is a classic poem about taking care of people who are sick and dying. And not just any people, either, but soldiers.
Like Unbroken, "The Wound Dresser" is about a war (the Civil War in Whitman's case) that happened before the term PTSD became common knowledge. But that doesn't mean it didn't exist, and Whitman almost seems to be alluding to it here, the "curious panics of hard-fought engagements" that seem to stick with veterans.
In many cases, it's easier to dress the physical wounds that come from battle. But how does a caretaker heal the emotional wounds? In Louie Zamperini's case, it's by telling his story.