The speaker looks back on a life measured out in hats. There was one for every matter: showing off, braving wind, keeping the peace, going to war, even hurting someone. The list moves quickly from the everyday to the serious, and the hats start to sound less like clothing and more like roles or attitudes the speaker put on to meet the world.
Then the poem slows down. The last hat is simply "for this rain," and it keeps the speaker company until night. After all the grand occasions, the final line feels quiet and almost tender. The past tense of "had" suggests the speaker is remembering, though the rain seems to be falling now.
The mood is calm, a little wistful, and lightly humorous at first, then more reflective. The speaker doesn't dwell on the harm or the war, and that restraint is telling. What remains is a small, ordinary comfort: a hat, some rain, and the hours passing toward evening.