The cast and director of 'Platoon,' from left, American actor Tom Berenger, American director Oliver Stone, American actor Charlie Sheen, and American actor Willem Dafoe arrive for the screening of the film 'Platoon,' at the 59th International film festival in Cannes, southern France, on Sunday, May 21, 2006. (AP Photo/Laurent Emmanuel)

CANNES, France - When his Vietnam saga "Platoon" appeared, Oliver Stone felt it was a painful reminder of an aggressive mentality he hoped America had left behind.

Two decades later, the country has fallen back on old habits, Stone said Sunday at the Cannes Film Festival, where "Platoon" had a 20th anniversary screening in advance of a new DVD edition coming May 30.

A semi-autobiographical account of Stone's infantry experiences in Vietnam, "Platoon" depicts the combat with terrible savagery. With the current war in Iraq, the message has gone unheeded, said Stone, whose film won four Academy Awards, including best picture and director.

"It's a shame, because you make these movies, you hope that they will make people more conscious about what war is," Stone told The Associated Press in an interview alongside his three stars, Willem Dafoe, Charlie Sheen and Tom Berenger. "It did work, and it went around the world like a shock. It made all our careers.

"Twenty years later, actually 10, 15 years later, it started to change again. People forget, and they drifted back to a militaristic point of view. ... By the time Iraq came around, `Iraq 2," I was pretty depressed."

The Cannes screening of "Platoon" was preceded by footage of Stone's upcoming film "World Trade Center," starring Nicolas Cage in a Sept. 11 drama about two policemen trapped in the rubble of the twin towers after the terrorist attacks.

Due out Aug. 9, "World Trade Center" is the year's second big-screen film centered on Sept. 11, 2001. "United 93," which opened in the United States in April and also is playing the Cannes festival, was a stark docudrama about passengers killed in the crash of their plane after they fought back against their hijackers.

Stone said the "World Trade Center" footage is a fitting companion to "Platoon," the two films offering closeup views of war or terrorism in the trenches.

"It is a return to the working-class heroes, people who confront reality at this ground level," Stone said. "When you actually get down and see what these men did in that hole, and their families, it makes it more human, and it makes you understand what war is and what terror is."

"Platoon" is the story of a raw infantry volunteer (Sheen) who enters his tour of duty with innocent optimism but soon learns the harsh reality that the only cause worth fighting for is survival. He becomes a pawn in a power play between two sergeants, one (Dafoe) who has maintained his humanity despite losing his idealism, the other (Berenger) a man who has become a cold-blooded killing machine.

The soldiers depicted in "Platoon" were aimless, doing battle for the sake of doing battle, having lost any sense of purpose or objective, Berenger said.

"The classic comparison would be the Greeks and the Trojan War," Berenger said. "They're outside the walls of Troy, fighting, fighting, fighting, and then fighting among themselves. They begin to forget what they were there for."

Stone put the actors through rigorous boot camp to train for the roles, depriving them of sleep and trying to give them the edge of irritability that comes with jungle combat.

"I think we got a real sense of, save for the actual life and death aspect of being in a combat zone, that we were in a real conflict," Sheen said.

"And the thing that sucked for me was in that training camp, during those two weeks, you had to maintain your rank in the movie," said Sheen, whose character was the low-ranking new boy. Nodding at Dafoe and Berenger, Sheen added, "And you guys weren't nice. You weren't nice to me."