One of the most iconic pictures from WW II was the raising of the US flag at Iwo Jima. (The other cool flag raising picture from the same war, in my opinion was from Berlin.) It's a technically brilliant photograph which really captures the feeling victory. The government saw this as a chance to raise money for the war bonds. So, the three survivors from the flag raising were taken back to the US and feted and treated as heroes.
The movie is a story of the photograph and the three men. It is told in a non-linear manner through the recollections of the different people involved in the photograph. I wouldn't call it an anti-war or a pro-war movie. It seeks to tell a very real story of what happened during the war.
It has been directed by Clint Eastwood and co-produced by Speilberg. I really enjoyed it and look forward to the companion movie, Letters from Iwo Jima, also by Clint Eastwood.