If you've heard one war story, you haven't heard them all. War Horse changes things up because its narrator is a horse. And he's not a person trapped inside a horse's body. He is full-blown horse. He relies on non-verbal communication, so what is said is less important than how it is said. But despite being an entirely different species (and therefore emotionally distant and lacking introspection), Joey is surprisingly relatable.
How would the story be different if it were told by a regular ol' human?