Letters from Iwo Jima is clearly superior to its companion piece, Flags of our Fathers, and I would hesitantly include it in the pantheon of superb war epics, with a few qualifiers. The combat sequences are at turns breathtaking (sweeping ariels of the island as it is bombed and shelled) and shockingly brutal (bayoneting and other close quarter fighting). The action sequences are technically more impressive than Flags of our Fathers, but they are not quite on par with the bloody, kinetic frenzy of master works like Black Hawk Down, Saving Private Ryan or Band of Brothers.
But then of course, this is not primarily a combat film. It is a deeply disturbing psychological exploration of the horrific realities of combat, and I think it is very successful in sucking you into the mindset of the Japanese soldiers as they await their deaths. There is one particular scene inside a cave when Mt. Suribachi is lost that is extremely effective in conveying that sense of impenetrable terror. Fortunately for us, the viewer, we can pause the scene, turn it off, or at least know that in a few minutes it will be over. Not so for the soldiers.
The film is less effective as a portrait of traditional Japanese notions of honor for one big reason: the two Japanese officers who have extensive experience living in and socializing with Americans are portrayed as the most enlightened, while virtually all other Japanese officers are portrayed as brutish and almost imbecilic in their convictions. Now, I'll be honest, I don't know enough about Japanese culture to say whether this is a bit of patriotic American bias bleeding through, or whether it is a reasonably accurate representation of historical fact. But keep in mind, this film was made by an American production company. It just seemed to my untrained eye that the characterization of the Japanese was a little off.
A minor criticism however, as the main empathetic thrust of the film is very effective and very well done. All in all, this film is extremely well rounded, with a nice balance between both heroic and disgusting combat sequences; warm personal vignettes giving backstory into the characters; and deeply soulful meditations on a soldier's life and death on the battlefield.