Take a story's temperature by studying its tone. Is it hopeful? Cynical? Snarky? Playful?
Resigned, Weary, Objective
Thomas Fowler, the first person narrator, thinks of himself as a reporter, someone who writes about what he sees. He tries to describe and explain objectively, from a distance. Of course, he's reporting to us about himself, someone he's deeply invested in. He lets us know his likes and dislikes. He's also not afraid to judge himself or report to us his judgments of others.
His reports, however, are not without attitude and feeling. He's grown tired of life and loss and fear, and his weariness shows. After learning that he's to be promoted and taken away from Vietnam, he laments:
I envied the most homesick officer condemned to the change of death. I would have liked to weep, but the ducts were as dry as the hot-water pipes. (1.5.1.36)
Fowler doesn't see much hope for himself. Just look at his final line, which expresses a wish that has gone unfulfilled:
I wished there existed someone to whom I could say that I was sorry. (4.3.3.48)
Fowler seems resigned to a fate racked with guilt.