The Tokyo International Film Festival opened this evening with a bang. There was of course the star-studded red carpet ceremony that saw many of the luminaries of this year's event walking down the long crimson avenue that was laid on Saturday afternoon between Roppongi Hills' soaring office buildings and residential towers. But the explosions that confronted audiences in Clint Eastwood's recreation of the brutal 1945 battle of Iwo Jima proved an equally important part in the launch of what is the most serious and challenging festival program in recent memory.

On February 19, 1945, 30,000 US marines assaulted the beaches of Iwo Jima and began to engage the island's 22,000 Japanese defenders who emerged from an extensive system of caves in which they had withstood months of withering bombardments from air and sea. It was the start of a brutal 35-day battle, one of the bloodiest single engagements in the history of warfare. By the end of it close to 7,000 Americans and 18,000 Japanese were dead, with over 20,000 wounded on the American side.

But numbers can only hint at the battle's true cost. Eastwood's reconstruction of the mayhem and sheer destructive power of modern armed conflict manages to say a great deal more, and it must count among the most terrifying portrayals of warfare and its tolls, both physical and mental, in the long annals of film history.

As the movie's catchphrase puts it, "a single shot can end the war," a fact which is viciously demonstrated in one particular 15 minute stretch of the film when many of the young men Eastwood has depicted surviving the first hellish assault are with little ceremony picked off one by one as they fight to secure the island.

"Flags of our Fathers" does not remain on Iwo Jima for its entirety, however, following as it does the fate of the three surviving members of the group of servicemen that the AP photographer Joseph Rosenthal captured in his iconic photograph of five marines and one navy corpsman raising "old glory" at the top of Mt. Suribachi on the fifth day of the month-long battle.

The power of that image to encapsulate the heroic struggle of Americans fighting in the Pacific was quickly recognized by military propagandists and politicians who were anxious for some new means of rallying a population that had grown tired of the war for the last push towards victory.

To that end the last three men alive in Rosenthal's picture were snatched from the ongoing battle and sent on a whirlwind tour of the United States where they gave speeches, recreated the flag-raising on faux papier-mache mountains and coaxed men and women across the country to dig deep and buy government bonds to support the war effort.

Throughout his patient telling of this complex and tragic saga Eastwood doesn't flinch from bringing his underlying message home. War is hell not only because of the bombs and bullets and the painful, untimely death of untold innocents, he seems to be saying, but because it makes men become what they should never have to be: wide-eyed witnesses and perpetrators of sheer barbarity.

Primo Levi once wrote of the millions of people that experienced the holocaust in Europe, "those who saw the bottom of hell, those who saw the Gorgon, have not returned to tell about it, or if they did come back they were muted."

And so it is for the tortured survivors of the flag-raising, who speak not at all, or only to insist they are not heroes, that "the true heroes of Iwo Jima are dead on that island," as one of them puts it with a hint of anger in front of an eager and patriotic audience in New York's Times Square.

"Flags" will be followed later this year by Eastwood's second film about the battle, the Japanese-language "Letters from Iwo Jima" that tells the story from the Japanese perspective, with Ken Watanabe staring as the island's garrison commander.

"Letters from Iwo Jima" is the result of what Eastwood called his sense during the filming of “Flags” that he was only telling half of the story. Indeed, except for a few fleeting scenes in “Flags of our Fathers” when they rise from their underground defensive positions to conduct suicidal charges and throw themselves into American positions, the Japanese are totally unseen. For the most part one is left only with a vague and unsettling notion that actual human beings buried beneath the earth are responsible for the withering machine gun and artillery fire that seems to hurtle forth from the Island itself to cut down the advancing marines.

Audiences here in Tokyo will no doubt be anxiously awaiting Eastwood's second telling of one terrible event in human history that if remembered, and even partly understood, calls on us all to work so that it need not happen again. Given the state of the world today that is perhaps a naive notion, but "Flags of our Fathers" insists that it remains a vital one.