The fact-based action movie 12 Strong touts itself, a little breathlessly, as the "declassified" story of a daring 2001 mission in Afghanistan.

Yes – it's declassified, but not recently. The movie's been in the works for five years, and in fact is adapted from the 2009 Doug Stanton book The Horse Soldiers about special forces operating in northern Afghanistan in the early days of the war, just a few weeks after 9/11.

Still, it's a pretty good yarn. The U.S. military was looking to catch the Taliban off guard, and to that end called upon a unique special forces group to team with anti-Taliban factions to capture the key northern stronghold of Mazar-i- Sharif.

The Fifth Special Forces Group was trained for just such a mission – able to speak various languages and dialects, to engage in on-the-ground diplomacy, to work with civilian populations, to travel lightly, and use the tools available to fight in enemy territory. (In real life, the unit had no time to requisition supplies through the army, so they bought most of their GPS gear and survival equipment at the retailer REI.)

All necessary skills in northern Afghanistan 2001. Al Qaeda had taken the precaution on Sept. 9 of assassinating Ahmad Shah Massoud (his picture is seen briefly in early scenes), the leader of the shaky "Northern Alliance" of Taliban-hating Afghan tribes.

When Capt. Mitch Nelson (Chris Hemsworth) arrives, he finds a splintered alliance, plagued by rivalry, suspicious that the United States might favor one faction over another, and unsure the Fifth Group soldiers have the ability to help them dislodge the Taliban.

Nelson finds himself in a uneasy relationship with Northern Alliance Gen. Abdul Rashid Dostum (Navid Negahban), his putative ally and Afghan collaborator. Early scenes have each man probing the other's bona fides. To boot, Nelson has to prove himself to his own men (including Michael Shannon and Michael Pena, coincidentally both stars of  World Trade Center), most of whom have seen more action.

It helps that Nelson is the only special forces soldier able to ride a horse — the only method of transportation available in the rugged, trackless terrain between the Northern Alliance factions and the Taliban they intend to fight. He gives his men a two-minute equestrian lesson, and off they go.

This is all drawn from life. And while 12 Strong leaves out many details, much of what you see on screen is accurate — including the incredible moment when Dostum uses fancy special forces communications equipment to raise his Taliban opponent on the radio, essentially to talk smack.

Dostum has some reason to be cocky. Part of the job of Nelson's assignment is to locate Taliban forces and call in smart-bomb air strikes from B-52s flying miles overhead. But there is plenty of old-fashioned fighting to come — so old-fashioned it takes the form of 18th-century cavalry charges.

Director Nicolai Fuglsig has a background as a combat photographer, but he's been drawn into the stylistic orbit of producer Jerry Bruckheimer, so the movie is glossy and slick, and generally designed to make combat look video-game awesome. But in essence, it shows that what the "horse soldiers" did was pretty remarkable — efficient, daring, effective. Of course, that model of efficiency was not sustainable, and Afghanistan has become an expensive and essentially permanent exercise in nation-building. (Puerto Rico could probably solve its rebuilding problems by discovering Taliban on the island.)

Also, the practice of fighting wars with special forces units has caused many to become stretched thin, causing alarm even within the military.


12 Strong

    • Directed by Nicolai Fuglsig. With Chris Hemsworth, Navid Negahban, Michael Shannon, Michael Pena, and Trevante Rhodes. Distributed by Warner Bros. Running time: 2 hours, 10 min. Parent's guide: R (violence). Playing at: Area theaters.