It’s been almost nine years since Kimberly Peirce’s breakout film “Boys Don’t Cry,” so expectations for her new project were bound to run high. Alas, she doesn’t do herself any favors with the self-serious, emotionally hollow “Stop-Loss.” Why would someone who’s so selective about the films she makes choose something so uninspired?

The title refers to the U.S. Army’s policy of renewing soldiers’ enlistments against their wishes, a necessary step when new recruits are in short supply and there’s a war going on. Technically, the war in Iraq ended years ago, but this hasn’t stopped the military from hanging on to thousands of soldiers who were supposed to have gone home when their time was up.

“Stop-Loss” is a fictional story about a real crisis, written by Peirce and Mark Richard and starring Ryan Phillippe as the soldier who gets stop-lossed. His name is Brandon King, and he has just returned to his hometown of Brazos, Texas, after a firefight in Tikrit that left some of his men dead or wounded. Brandon is a model soldier and staff sergeant, even to the point that his saintliness strains credulity, but he snaps when he learns he’s being sent back. He tells his commanding officer (Timothy Olyphant) that he refuses to go, then flees the Army base.

Brandon believes his one chance of overturning the Army’s decision is to enlist the help of a Texas senator he once met. To that end, he heads for Washington D.C. with Michelle (Abbie Cornish), the fiancee of his best friend and fellow soldier Steve Shriver (Channing Tatum). Meanwhile, back in Brazos, Steve is having some serious post-traumatic stress disorder, and a third Army buddy, Tommy Burgess (Joseph Gordon-Levitt), is still reeling from the death of a friend back in Tikrit.

Like the post-Vietnam dramas of 30 years ago (particularly “The Deer Hunter”), “Stop-Loss” seeks to show the horrors of war not by depicting battles but by peering into the minds of the soldiers who survived them. Yet Peirce’s attempts to show Steve’s PTSD hallucinations and Tommy’s internal struggles fail to hit home, and the characters — though well played by Tatum and Gordon-Levitt — come off as tertiary rather than as part of the ensemble. They’re not quite the focus, but not quite minor figures, either.

Phillippe fares better as Brandon, with a convincing Texas accent and more opportunities to show the character’s depth of emotion. Brandon feels guilty about how he led his men in Tikrit and betrayed by the Army for pulling the rug out from under him, and he earns the audience’s sympathy whether we agree with his going AWOL or not. Phillippe has yet to persuade the American public that he has the charisma, talent, and gravitas necessary to successfully carry a serious drama … and I’m not sure this will persuade them, either. But it’s a step in the right direction. He’s certainly come a long way since “Cruel Intentions.” (Then again, haven’t we all?)

It’s Peirce’s handling of the material that falls short. The tacked-on title cards at the end announcing statistics on the stop-loss program bring heavy-handedness to a film that otherwise mostly avoids the soapbox. But on the other hand, considering how mealy-mouthed the movie is, maybe a little indignant preaching would have improved it (or at least made it more love-it-or-hate-it). As it is, Peirce crams the story full of content — events, plotlines, and characters — but not much actual meaning. Rather than provoking discussion of important issues, the film provokes almost no response at all.

C+ (1 hr., 52 min.; R, pervasive harsh profanity, some graphic violence.)