“American Sniper” has great credentials. Nominated for six Academy Awards, it’s based on a popular memoir by an American military hero, Chris Kyle. It stars Oscar nominee Bradley Cooper and it’s directed by the legendary Clint Eastwood.

Even the trailer for “American Sniper” is terrific, with Cooper/Kyle peering through the crosshairs, with a finger on the trigger, as he zeroes in on an Iraqi boy who may or may not be carrying an explosive device in the direction of vulnerable American troops. The tension is palpable.

Unfortunately, that tension dissipates over the course of a two hour movie. In other words, the high expectations for “American Sniper” are not quite met.

Navy SEAL sniper Chris Kyle served four tours of duty in Iraq in the years following 9/11. He’s officially credited with the most “kills” in American military history, 160. His marksmanship became the stuff of legends.

The movie dutifully covers each of the four tours, each highlighted by one particularly dramatic incident. On one tour, he confronts a bloodthirsty terrorist who kills with an electric drill; on another, he squares off with an enemy sniper every bit as good as he is.

Overall, the action scenes in Iraq are quite effective: tightly shot firefights, tense stakeouts, risky door-to door patrols. Eastwood does a good job highlighting the war zone dramatics without glamorizing the action.

To his credit, Eastwood and screenwriter Jason Hall are not content just making an exciting war movie. They’re equally interested in the home front. Kyle has a girlfriend, who then becomes his wife, who then becomes pregnant, who then becomes mother to Kyle’s son.

Not surprisingly, she becomes more and more unhappy that the love of her life keeps leaving her time after time after time to serve his country. There’s a lot of pleading and a lot of tears, each time with more and more desperation.

While that may ring true emotionally, dramatically it just gets tedious. Eastwood can’t figure out a way to make the wife’s stress at home as palpable as her husband’s stress on the battlefield. (There’s one exception: a scene in which the two are talking by satellite phone when his convoy is attacked.)

It’s not just an undeveloped wife that’s problematic in the script. Kyle himself is equally underdeveloped whenever he’s back home. Similar to The Hurt Locker, Kyle feels out of sorts at home. Understandably he can’t square the mundane lives most of us live here with the high-octane life he experiences on the battlefield. When he’s required to see a psychologist to check out whether he’s suffering from PTSD, he brushes off the notion with heroic words about how he just wishes he could have saved more lives.

Eastwood deserves credit for hinting at the difficulties of a soldier’s reintegration into society but he doesn’t seem all that interested in exploring it too deeply.

What is the effect on a man who kills 160 people, one at a time, and witnesses the deaths of dozens and dozens of colleagues? Is it really so negligible? Maybe so, but then that too is worth exploring. Eastwood keeps us at arm’s length from Kyle’s internal processes.

This becomes even more important in light of the bizarre way Kyle’s story ends. I don’t want to give anything away in case one’s unfamiliar with his story, but it begs for more insight than the film provides. Without it, what happens at the end of the movie just seems random and arbitrary, rather than potentially revelatory.