Rarely has a film been as timely as “Restrepo.” Just as the US involvement in Afghanistan has once again become front-page news—not just because of a dramatic change of command but because of increasing casualty rates and heated debate about the very nature of the mission—this stunning, fly-on-the-wall documentary shows what the combat experience is actually like for American soldiers there. It’s a harrowing, deeply troubling and thought-provoking film, but not a tub-thumping, didactic one.

The film is the work of journalist-author Sebastian Junger and photographer Tim Hetherington, who separately traveled to the Korengal Valley at various times during 2007-2008 to film members of the Second Platoon, Battle Company of the 173rd Airborne Brigade as they manned a remote camp in the dangerous eastern mountain region. The footage is of the verite variety, showing the men digging in, enduring sniper fire, engaging with locals, and going on recon missions.

In the process there are casualties, one of them Pfc. Juan S. Restrepo, a medic killed early in the deployment, after whom the squad named a smaller outpost they built, with great difficulty, on a strategically useful ridge. Interspersed with the moments of tension and action are many others of roughhousing and simple boredom. After the deployment was over and the soldiers returned from the front lines, the filmmakers interviewed the men, and their recollections are inserted into the footage of their tour. Their memories often focus on one of their incursions into potentially hostile territory, an operation called Rock Avalanche, in which things did not go well.

There’s nothing at all slick or superficial about “Restrepo.” The footage is rough and sometimes grainy, and there’s no effort to impose a spurious dramatic arc on it; it’s merely presented as it happened. Nor do the filmmakers politicize the material. Questions about the policies behind the deployment aren’t raised, except in the most indirect way; the men don’t discuss why they’re where they are, or debate the American presence in Afghanistan, even in the post-tour interviews. When they speak, it’s about their combat experiences, not about the right or wrong of the war, and without rancor. And yet it’s impossible not to feel how deeply those experiences have seared them.

And though the film doesn’t make obvious judgments, it’s not without interest that the outpost where the men were stationed has since been abandoned, and along with it all the pledges of improvements with which the soldiers vainly tried to persuade the locals to reject the insurgents and support the Karzai regime. That fact speaks to the futility of their mission—and the policies behind it—better than any overt message could. And at a moment when the casualty rate in Afghanistan is higher than ever, “Restrepo”—easily one of the best films about the post-9/11 conflicts, fiction or documentary—deserves the largest possible audience.