The psychological toll of war on US soldiers is depicted in grainy black-and-white footage, a young American soldier from World War II struggles to express his feelings in a wrenching scene from a new documentary.
"I can't stand seeing people killed," the soldier eventually manages to say, averting his eyes.
Despite the film's unflinching take on combat stress, top military brass hosted the premiere of "Wartorn: 1861-2010" Thursday at the Pentagon, illustrating a shift in commanders' attitudes to a problem once dismissed as a sign of weakness.
The unusual venue and audience, which included the country's highest ranking officer, Admiral Mike Mullen, as well as families of troubled soldiers depicted in the film, underscored how military leaders are now ready to confront the "invisible wounds" of the wars in Iraq and Afghanistan.
"What's interesting is the way in which the military is embracing this, and that they're choosing to show this at the Pentagon," said Jon Alpert, the director and producer.
"They're choosing to talk about this openly, really for the first time," he told AFP.
The documentary recounts how senior officers in another era had little patience for what was called "battle fatigue" in World War II.
In that conflict, General George Patton slapped a soldier hospitalized with "nervous exhaustion."
"I won't have the hospitals cluttered up with these sons of bitches who haven't got the guts to fight," Patton said.
World War II veterans in the film recount how they are still haunted by their battle experiences, and that they felt deep shame over their mental state on their return.
"In the old days it was called battle fatigue and it was a no-no. Nobody wanted to get stuck with battle fatigue," says veteran Rocco Moretto.
The Pentagon screening demonstrated how much the approach of military leaders has changed since Patton's outburst.
Mullen, chairman of the Joint Chiefs of Staff, who delivered opening remarks at the premiere, has made a point of focusing on combat trauma and rising suicides, calling for end to the stigma sometimes associated with seeking counseling.
"Sopranos" star James Galdofini served as the executive producer and appears in the documentary interviewing top generals and soldiers about post-traumatic stress.
In one scene, General Peter Chiarelli, the US Army's vice chief of staff, tells Galdofini that soldiers with psychic wounds need to be taken off the battlefield with the same urgency as a warrior who has lost a limb.
"Only bad things happen when you wait to treat an injury," the general says.
But he admits that the military's traditional mindset remains an obstacle.
"You're fighting a culture, a culture that really doesn't believe in these things," Chiarelli says.
The film juxtaposes traumatized veterans from Iraq and Afghanistan with their predecessors in past wars, sharing similar symptoms and nightmares.
"Wartorn" begins with letters from a young soldier fighting for the Union army in the civil war, Angelo Crapsey, whose enthusiasm gradually gives way to despair at the sight of so much bloodshed. He is hospitalized and then later sent home, where he commits suicide.
The documentary is a far cry from the military's slick promotional campaigns on television that are filled with appeals to heroism and duty.
The film's sobering true stories include service members who decide to end it all after tours in Iraq, and one marine sentenced to prison for attacking a Middle Eastern taxi driver at gunpoint.
"I'm not a good person. I have done bad things. I have taken lives," wrote 23-year-old Noah Pierce, shortly before he shot himself in the head as he held his dog tags to his temple.
His mother, Cheryl Pierce, blames the military for her son's deterioration.
"The United States Army turned my son into a killer," she says. "They forgot to un-train him."
As many as 30 percent of US troops may suffer from post-traumatic stress, General Ray Odierno, the former commander in Iraq, tells Galdofini.
"Nobody is immune," Odierno says.
The film, which is due to air next month on the HBO network on Veterans Day, November 11, could bring home the cost of war to many Americans who are mostly untouched by nearly a decade of conflict.
For William Fraas, whose 29 months of combat duty in Iraq left him scarred and anxious amid crowds, the simple act of shopping for groceries is an excruciating exercise.
His wife, Marie, says Fraas came back a changed man, mesmerized by photos from his tours and often detached from his family.
"He's home but he's not home, like he was."