Errol Morris makes documentaries that matter. Here he captures former Secretary of Defense Robert Strange McNamara, as the now 85-year-old presidential adviser and architect of 20th-century warfare both justifies and reassesses, on both moral and political grounds, some of the decisions he made that affected the lives of millions of people. The film unfurls in 11 individual “lessons” with titles such as “Rationality will not save us” and “You can’t change human nature.” While Morris complements his subject’s reflections with imaginative, mind-tingling visuals, McNamara serves up his version and numerous little-known facts about the Cuban missile crisis, our devastating firebombing of Japan before our A-bomb drops, and our Vietnam blunder, with articulate precision. McNamara was, at one time, one of the most powerful, ridiculed and despised men in America. Morris allows him the freedom to tell his story as well as to shoot himself in the foot.