(CNN) -- Who says that history is written by the victors? It wasn't long after President George W. Bush declared "Mission Accomplished" in Iraq that the triumphant narrative he'd constructed began to unravel.
Turned out the president was several years premature in announcing the beginning of the end. Even the beginning wasn't over. The reasons we'd gone to war in the first place would be debated more ferociously in retrospect than they ever were at the time, not least because the notorious WMD never did materialize.
That disappearing trick is at the heart of "Green Zone," a revisionist Baghdad thriller from the Jason Bourne team: star Matt Damon and director Paul Greengrass.
Damon plays Chief Warrant Officer Roy Miller, who's disgusted by the bad intel. His men risk their lives to turn up biological, chemical or nuclear weapons, but every time they come back with a big fat doughnut.
People keep telling Miller to stop asking questions and do his job. Instead, he listens to an Iraqi informant who leads him to the doorstep of a Ba'athist general, one of Saddam's right-hand men. The general escapes, but he won't elude them for long, and his discovery will surely bring the truth about WMD out into the open ...
Filmed in the same jittery gun-it-and-run-it mode as the "Bourne" movies, "Green Zone" plunges headlong into the ethical no-man's-land between action movie escapism and political drama-documentary.
Greengrass made "United 93" between Bourne assignments, and he seems persuaded that one style fits all. (Heaven help us if he ever decides to tackle a love story.) It's exciting in fits and spurts, but it becomes tiresome over 115 spasmodic minutes.
Shot by Barry Ackroyd (who also photographed "The Hurt Locker"), the film reconstructs the destruction of Baghdad out of bits and pieces of Morocco and Spain.
Maybe there's too much street lighting -- wasn't the city without power for long stretches in the weeks and months after the invasion? And like many a movie star soldier before him, Damon seems curiously unattached to his helmet. But the scale is genuinely impressive, and the film gives the sense that the whole country is a powder keg of ethnic tensions and resentments the Americans scarcely comprehend.
Despite what the credits may claim, Brian Helgeland's script isn't really based on Rajiv Chandrasekaran's "Imperial Life in the Emerald City." The book is first-person reportage by The Washington Post's former Baghdad bureau chief, and you won't find "Roy Miller" in its pages, nor the mid-level conspiracy he stumbles across.
Maybe Robert Altman could have done justice to Chandrasekaran's tragicomic snapshots of the surreal dissonance between the luxurious comforts of home enjoyed by the American administrators occupying Saddam's former palace and the rampant anarchy just outside the Green Zone perimeter.
Greengrass catches it on the fly -- when Miller comes in, bruised and bleeding from the battlefield, and walks into a scene resembling cocktail hour poolside at the Bellagio -- but he's not a natural ironist; he takes no pleasure in it.
Still, the movie accurately reflects the book's central thesis: that the Iraqi insurgency was a byproduct of an American civil war and the ascendancy of neocon crusaders (represented here by Greg Kinnear's security adviser) over the State Department's seasoned diplomats (Brendan Gleason as a CIA Middle East expert).
Whether you agree with that assessment or not, the movie feels underplotted and overdetermined. The American press corps is reduced to one fictional correspondent. The Iraqis get a couple of speeches to vent their anger, and it's left to Matt Damon to expose the truth about all the lies.
The argument adds up, right down to the last, teasing shot of the oil fields, but "Green Zone" falls over itself in its eagerness to explain what went wrong over there.
Unlike "The Hurt Locker", this finger-pointing doesn't involve any real soul-searching.