Peter Ericson’s review published on Letterboxd :
Another movie about the unquestionable fact that war is hell? Well, yes, "American Sniper" is that too, but the primary focus of the film lies elsewhere.
Director Clint Eastwood and screenwriter Jason Hall (the script is based on Chris Kyle’s autobiography, co-written by Scott McEwen and Jim DeFelice) seem less interested in depicting the horrors and calamities of war—although they certainly don’t avoid doing that—and more concerned with the psychological effects that war has on soldiers in general and had on Navy SEAL sniper Chris Kyle (Bradley Cooper) in particular. Any story details that the filmmakers have added, glanced over, or omitted don’t necessarily invalidate the truth of that central theme of the proceedings.
Eastwood wisely stays clear of taking a firm moral or political stance with "American Sniper" on the big-picture questions raised by the movie, instead leaving it up to the viewer to decide for themselves. While it contains some undeniable—and admittedly unavoidable—elements of patriotism, the film doesn’t register as being jingoistic, at least not to this non-American viewer. I do, however, take issue with the protagonist–antagonist portrayal of Chris and Syrian sniper Mustafa (Sammy Sheik), which unfortunately comes across as too much of a cinematic contrivance.
Furthermore, Chris isn’t really presented as a hero here, although some of the other characters in the movie regard him as such. In fact, in one home-life scene set at a garage, he is clearly uncomfortable when confronted by a war veteran who praises Chris for his—in the eyes of said veteran—acts of heroism.
There are a number of tense scenes in "American Sniper". The film opens with an effective, edge-of-the-seat suspenseful scene that puts the viewer right in the middle of the action, then uses flashbacks to establish the backstory. Two hard-to-shake moments involve a young boy who tries to pick up a rocket launcher and another young boy who is tortured with a power drill, respectively; truly harrowing stuff. The climactic battle, which takes place in a sandstorm, is excellently executed and sure to get one’s pulse racing.
Its notable war scenes notwithstanding, "American Sniper" works best as the character study it is at its core. If only the film had dared to venture deeper into the psyche of its subject, the end result could have been a great, powerful movie with more dramatic weight than the current one.
"American Sniper" ends abruptly, but how could it possibly have ended any differently? A little more information would have been welcome, but I presume all the details aren’t in. Besides, the ending obviously has thematic relevance.
Whatever flaws the viewer may find in the film, the acting definitely isn’t one of them. As Chris, Bradley Cooper is very good, capably and convincingly playing a man who suffers from posttraumatic stress disorder. And Sienna Miller shines in the role of Chris’s wife Taya, her nuanced performance conveying what life is like for someone whose partner has been deployed to a foreign country.