Vince Lombardi must be turning in his grave. Although Friday Night Lights takes a surprisingly unsentimental look at the religion of high school football in Texas, where combat metaphors are dead serious (“We are in the business of protecting this town”), the film concludes dishonestly that winning isn’t everything. Based on a controversial book recounting the 1988 season of a little team that could, the story gestures at a cross-sectional view of America on a Nashville scale. But in a hot desert, pockmarked by oil drills and other fraudulent totems of imagined glory days, Robert Altman’s indie cynicism would feel unduly cruel. Instead, director Peter Berg, an actor himself, gets quietly excruciated performances from the team members that indemnify the traces of studio optimism (and he makes the best cinematic use of Public Enemy since Spike Lee). As the emotional lightning rod of a coach who carries the weight of a town’s broken promises on his face, Billy Bob Thornton mesmerizes again.