Corrections and Clarifications: An earlier version misspelled the last name of one of the soldiers. He is Andy Marchal.

FORT CAMPBELL, Ky. — Within hours of the 9/11 attacks, 12 men from America’s most elite forces were gearing up to head into a place they knew nearly nothing about with the weight of a nation on their shoulders.

Geoff Stults, left, shows off a personal photo with Chris Hemsworth while shooting '12 Strong.'
Courtesy of Geoff Stults

Thousands had died in New York, Washington, D.C. and Pennsylvania, and at this sprawling military post, one of the few immediate response teams tasked with taking down the Taliban regime was forming as millions of other Americans grieved over the loss of life.

The story of that first response, and what a single 12-man team from Fort Campbell's 5th Special Forces Group did in northern Afghanistan on horseback will be among the season’s biggest Hollywood releases in 12 Strong, which stars Chris Hemsworth, Michael Shannon, Michael Peña and Elsa Pataky.

The film by Jerry Bruckheimer, based on the book Horse Soldiers by Doug Stanton, was screened Sunday for a theater full of current and former members of that 12-man team and others in America’s most elite Army units based here.

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The film debuts in theaters Friday.

Almost all of the troops ordered into Afghanistan in the immediate aftermath of 9/11 came from Fort Campbell, including helicopter pilots from the 160th Special Operations Aviation Regiment.

Operational Detachment Alpha 595 — one of several “A-Teams” sent to Afghanistan in the days following 9/11 —  was given one two-part mission: Work with Afghan forces and destroy the Taliban regime, a strategy still being perfected on a larger scale today.

Retired Lt. Gen. John Mulholland led a team of Green Berets and is among the main characters depicted in the film "12 Strong."
Courtesy 5th Special Forces Group

“That was intimidating, yeah, and of course you realize you’re carrying the weight of the nation,” said retired Lt. Gen. John Mulholland, then a colonel who led the team into northern Afghanistan.

“Go do this, but you know, everyone dies here,” he said, referring to the fates of numerous armies dating back to Alexander the Great and Genghis Khan and later the British in the 1800s and the former Soviet Union in the 1980s who have failed in Afghanistan.

These 12 solders were outnumbered by the Taliban as they worked with Afghan rebels.

Mulholland, played by William Fichtner, is one of the few whose names weren’t changed for the film.

Andy  Marchal was one of those men on that mission. He doesn’t consider it any different than the other classified missions he was a part of during his 20-year career.

Andy Marchay, a former member of a Special Forces team depicted in the Jerry Bruckheimer film "12 Strong," attended a special screening Sunday, Jan. 14 at Fort Campbell.
Courtesy 5th Special Forces Group

“I didn’t see it as that big of a deal,”  Marchal said. “I did what I got paid to do.”

But they didn’t have any of the gear and technology that most Special Forces soldiers have today.

“We went into that fight with a shameful level of resourcing,” Mulholland said.

In the end, the soldiers overcame steep odds to secure the city of Mazar-i-Sharif, a landing strip and a critical northern supply route.

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Mulholland, who has seen the film a half-dozen times already, said some liberties were taken with the Hollywood production, which was expected. But he said the core of the story is true.

“I’m alive and anything they’re gonna show is gonna get you killed,” Marchal said, jokingly.

Mulholland said he hopes a much bigger message is delivered with the film, which is that when Americans band together and don’t worry about who gets credit, they can accomplish anything.

“There’s a lot of effort to divide us from one another, and it’s wrong, it’s evil and it’s detrimental to our country,” Mulholland said.

Follow Jake Lowary on Twitter: @JakeLowary