This is the second half of Clint Eastwood's bookend films about the Battle of Iwo Jima.
I found Flags of Our fathers to be a dud because of the multiple cases of "battleus interruptus". Everytime you thought a big Saving Private Ryan style battle was about it begin, *BAM!* you'd get tossed back stateside to watch Ira Hayes get drunk.
All the reviews for Letters say that it's a masterpiece.

