Spouting off to an empty chair at the 2012 Republican National Convention, Clint Eastwood looked as if he were slipping into doddering dementia, but he’s shrewder and more focused than ever in his Iraq War picture American Sniper. It’s a crackerjack piece of filmmaking, a declaration that he’s not yet ready to be classified as an Old Master, that he can out-Bigelow Kathryn Bigelow. Morally, though, he has regressed from the heights of Letters From Iwo Jima (2006). In more ways than one, the Iraq occupation is seen through the sight of a high-powered rifle. The movie is scandalously blinkered....