Screenwriter Bill Broyles Jr. (Cast Away) and director Sam Mendes (American Beauty) adapt Anthony Swofford’s existentially angsty Desert Storm memoir, but not especially well. Swofford has said he doesn’t mind the movie’s alterations, but the real issue is how it dulls the intimacy and idiosyncrasy of his voice, which was the book’s compass. As is his wont, Mendes uses archly poetic flourishes (a dreamed vomiting of desert sand, etc.) to hide his shortage of the real sophistication needed to assay this complex and contradictory material. The dreamy eyes of Jake Gyllenhaal, in the Swofford role, prove useful for the dramatized absorption of humiliation from variously debasing circumstances, and for the real absorption of identification from audiences. Still, the movie really belongs to the reliably excellent Peter Sarsgaard, who plays his buddy, Troy, and to the bleached void that is the Middle Eastern desert. Whether Jarhead will be, as Swofford writes of other war-related films, “pornography for the military man” is for us to decide. But his experience of war—as a sniper who never got a real shot off—was perhaps just emasculating enough to discourage its glorification.