Holy cow. War is hell.

A very sincere and heartfelt tribute to the American military, Lone Survivor is at its best when it’s recreating the terror and physical reality of battle. It’s less effective when it deviates from that spirit and indulges in myth-making and hero worship.

As the son of a military veteran who provided me with a decidedly irreverent (and off-the-record) perspective on the armed forces, I can respect the intent of Lone Survivor. Director and screenwriter Peter Berg sets a high standard for his own film to meet by beginning with a lengthy sequence of what appears to be documentary footage of Navy SEALs undergoing rigorous training. That segues into a scene of a medical team treating a battered and bloody soldier who is fighting for his life. That, in turn, leads to a ground-level view of the preparations for a SEAL team mission in Afghanistan in June 2005.

By its title, its opening sequences, and the knowledge that the movie is based on the real-life experiences of Navy SEAL Marcus Luttrell, we know that the outcome for the SEAL team will be disastrous. Just how dire, however, is what Berg and his team seek to recreate.

The SEAL team members and their comrades all have a similar appearance: male, often bearded, and very, very fit. Out of this group, four men emerge who will take the lead on the mission: the medic, Luttrell (Mark Wahlberg); the leader, Michael Murphy (Taylor Kitsch); the radio guy, Danny Dietz (Emile Hirsch); and the crack shot, Matt ‘Axe’ Axelson (Ben Foster). They’re all extraordinarily competent, and share a similar sense of humor and readiness to fight; under their camouflage, though, it’s sometimes difficult to tell them apart.

And that’s especially the case when their mission to capture or kill a Taliban leader goes horribly wrong. It’s a matter of time and chance; they’re in a thickly forested mountain range where communications with their headquarters is spotty at best, and when they come under fire, they are on their own against an overwhelming number of well-armed and well-trained enemy forces. Under fire, the SEAL team fights hard and doggedly, even when they are forced to retreat by (repeatedly) falling off the side of the mountain.

Those breathtaking scenes are exceedingly painful and distressing to watch, as we know the SEALs are breaking bones and opening gashes in their bodies, on top of the bullet wounds they have already suffered — and then they have to prepare instantly to defend themselves by taking cover and trying to kill the enemy fighters.

As acknowledged, we already know the fate of the men, and their actions have already proven themselves courageous under fire. By that point of the movie, their heroism is abundantly clear. So it feels like Berg and company are manipulating emotions when the end-point for each member of the team arrives and their final moments are drawn out in agonizing detail. It’s as though Berg doesn’t trust that the audience will understand on its own and reach the conclusion that he desires.

On the other hand, Berg doesn’t hesitate to plunge ahead with dialogue that is thick with unexplained military jargon and action sequences defined by military strategies, given without much context for the non-military viewer. In sum, it felt to me that the film skimps on explaining the military’s intent and double-downs on universal emotions that are blindingly obvious, resulting in a queasy and unsatisfactory ‘trust us, we’re the military’ conclusion.

Nonetheless, Lone Survivor is a very strong and stinging movie that provokes tremendous empathy and respect for the men (and women) who valiantly give of themselves for what they believe.

The film opens wide throughout Dallas and Ft. Worth on Friday, January 10.