Clint Eastwood is at the top of his game for about 10 action-packed minutes in which he directs a recreation of the events of Aug. 21, 2015, when three young American men thwarted a terrorist attack on a European train. Airman Spencer Stone, Spc. Alek Skarlatos and Anthony Sadler play themselves taking down an attacker (Ray Corasani), who’s armed with a knife, pistol, assault rifle and almost 300 rounds of ammunition. This unusual casting move boosts the action’s emotional heft, and those scenes are a tense, taut piece of filmmaking. But in the remaining 83 minutes of this movie’s brief...