It isn’t probable that Donald Rumsfeld’s memos are going to be collected in a volume for popular consumption. Unlike David O. Selznick’s. Selznick was perhaps the most prominent producer in the so-called Golden Age of Hollywood and the man who produced Gone With the Wind. He was also famous for his profusion of memoranda to directors, writers, and cinematographers, advising them of his take on their work as it progressed or didn’t. Often he’d visit the set to get a sense of what was happening. He may have thought of this as collaboration or protecting his investment. Some filmmakers regarded it as meddling. (Alfred Hitchcock was said to have pretended that the camera wasn’t working when Selznick showed up so he couldn’t tell what Hitch was really doing.)

Selznick’s memos are a varying compound of astuteness about commercial movie making, grandiose inconsistencies, and occasional strangeness. They were also sometimes funny, if unintentionally. So, years after his demise, Memo from David O. Selznick came out in hardcover.

During his six years as secretary of defense in the George W. Bush administration, Donald Rumsfeld wrote a lot of memos, perhaps 20,000, he estimates in Errol Morris’s The Unknown Known. And while there is inadvertent humor in them, the jokes pall very quickly. (Selznick never invaded Iraq or authorized brutal treatment of war prisoners.) Morris’s crafty, gradually, eventually sharply revealing documentary has Rumsfeld front and center.

The title comes from his famous nonsensically formulaic gloss on policy planning: “There are known knowns. There are known unknowns. There are unknown unknowns.” Judging by his self-assured on-camera demeanor, Rumsfeld seems to find this a piece of philosophical pith, instead of the pedantically empty poesy it is. His own reformulation of it—“That is, there are things that you think you know, that it turns out you did not”—is no Machiavellian update.

Although, when Morris breaks away to recap Rumsfeld’s career with archival selections, the impression of an office infighter and petty Machiavelli is created, as his subject schemes and jockeys for advantage through the Nixon, Ford, Reagan, and George W. Bush governments. As defense secretary under Ford, he cooperated with CIA director George H. W. Bush to inflate the Soviet military threat and promote a very expensive American military buildup that continued into the Reagan administration.

Rumsfeld’s is a genuine kind of American success story, with a rightist cast. His consistency as a proponent of American might and its corporate co-dependent has long been clear, though he tries here to come across as a technical, fact-seeking official. “I’m cool and measured,” he tells Morris. The central theme and interest of the movie, of course, revolve around Rumsfeld’s parts in the second Iraq war and the secret, probably illegal treatment of war detainees. He has rather obviously tried to appear friendly and open, but there are growing indications in this movie that his candor has real limits. His notorious December 2, 2002 memo on “enhanced interrogation” methods to be used on prisoners was issued, he claims, without his even reading the infamous opinion of the Justice Department’s John Yoo that the United States could ignore international conventions on torture. “What for?” he asks Morris. “I’m not a lawyer.”

Rumsfeld claims to have been guided by his historical studies, but his “readings” very arguably amount to distorted selectivity. At one point, he amiably accuses Morris of obsessiveness, but Rumsfeld provides stubbornly perverse and dangerously inappropriate comparisons between the Japanese Pearl Harbor attack and Iraq’s threat to the US. (The movie doesn’t address it, but the increasingly clear beneficiary of American blunders in the Middle East is the despotic Shiite regime in Iran.)

Rumsfeld has made a real effort at appearing receptive, reasonable, and friendly, and Morris has acknowledged this. Guesting on National Public Radio’s quiz show Wait, Wait, Don’t Tell Me, he said the former defense secretary was gracious and cooperative, but, asked if he liked him, he admitted he couldn’t. Rumsfeld’s frequent grinning has a dismissive and menacing quality. (The wolf in the Red Riding Hood story did come to mind.)

In his movie, Morris sometimes seems not to be pressing his subject, letting him have his self-serving say. But besides the use of countervailing film, video, and texts, there is Rumsfeld himself. Minute by minute, section by section, he indicts himself without understanding this.

Watch the trailer for The Unknown Known