'Syriana' is an amalgam of Middle East country names suggested by American foreign policy mandarins to brand what they must regard as one massive, US-culture sustaining oil field. In other words, 'Syriana' is what the gas station would be called if the world was small enough to call the Middle East a truck stop. It always struck me as either horrifically satisfying or proof God does irony that (a) the most powerful and progressive nation on Earth is utterly dependent on nations almost as far away from the US as they could be and (b) that the area is governed by what Jonathan Millar once bravely called (from an atheist's point of view) "…the biggest outdoor lunatic asylum in the world…" Millar also mused in his excellent series on disbelief that it seemed so incongruous that religious fanaticism fuelled the terrorist attack of 9/11 and yet a few hundred miles west from New York lay a heartland of such staunch religious belief that in this case, Christianity would give Islam a run for its dinar. And with a link Barry Norman would have been proud of, we go from dinars, to dinners…

In the desert, middle eastern working men argue for a place on the bus. A place on the bus means food on the table. The successful few are employed by a corporate oil company that could not care less about those who do its dirty work. In Tehran, an overweight, bearded American is doing shady arms deals with confident Iranians. An oil analyst gives the American TV stations what they want but is still beholden to the Saudi Emirs whose oil America depends on. The board of governors of a huge oil film (Connex) is astounded how a small firm (Killen) managed to secure a deal with Kazakhstan, a deal worth billions.

Now if that paragraph intrigues you, you are going to love every slow burning moment of Stephen Gaghan's masterful study of the global oil business and the men who bathe in it. Gaghan wrote Traffic for Soderbergh and if ambitious writers have another good script, it's only logical that they get a crack at directing it. Despite the credit that Syriana is based on the book, 'See No Evil: The True Story Of A Ground Soldier In The CIA's War On Terrorism' by Robert Baer (and Baer plays a small role in the movie), the American Academy have classified Gaghan's screenplay as 'original' and not adapted, a move that has mystified the writer/director. Gaghan does a wonderful job given that his two hour movie demands patience and an attentive ear for moments that turn on a dime. This is not a movie for the Van Helsing crowd. This is provocative and thoughtful film-making that dares to take the biggest subject of the 21st century and ram a reasoned and robust reality down the audiences' throat. The quote that began this review is no fantasy. Of course, it's a movie so there are certain dramatic licenses in place (I would so love the movie police to pull a film over and demand to see its dramatic licence) and these faceless corporate stooges and overlords can't all be the scum of the Earth… can they?

Think about oil for a moment. Oil is civilization, the west, the powers that be. Oil is the Duracell battery no Christmas should be without and we in 'the west' have had far too many Christmasses. Guess what? We've taken it for granted for so many decades that if it were taken away - as it will be inevitably - what happens then? Well, the US (understandably but not uncritically) isn't standing idle waiting for the Saudis to charge the Earth to maintain the land of the free and the home of the craving for oil. It's making deals and international business (a subject as far from my fields of experience as God is from Richard Dawkins) depends on those deals. Syriana is a film that explores what happens when conscience, ambition and naked greed all conflagrate in a vast ball of energy. Who comes out of it alive? I'll give you a clue. There are no bad guys but hey, they still manage to win.

Clooney plays overweight, bearded Bob. Bob is an American assassin who is able to do his job (in the first case without even blinking as a car goes up behind him) because he believes for good or ill, that he is on the side of right. The pitch white conscience he displays inures him against any sense that his country may not be operating with a clear moral duty. His methods are appallingly horrific (this is Dr. Ross, for heaven's sake). He plainly outlines the terrible aspects of his job as if he were a plumber advising a home-owner to fix a tap. A potential victim of a professional hit is to be poisoned. Bob fills in the rest. "Tie him up and then drive a car at him at 50mph…" All in a day's work for this creature of the blight, an unquestioning killer. But then Bob manages to get on the other side of his finely drawn line and let's just say that he'll never be able to get a manicure again without fearful shivers.

Mirrored in the narrative is the 'nice' family man oil guy. Bryan, played by Matt Damon, is an analyst who is devoted to his wife and kids and his company wants to send him and his family on a political jolly to Saudi to advise a soon-to-be Emir (played convincingly and attractively by Deep Space Nine's Dr.; Bashir, Alexander Siddiq) on how he should plan for the future. The results of the trip are accidentally horrifying. This particular tragic scene is directed and cut in such a superb way, it manages to deliver on three fronts. It propels the narrative forward, deepens those characters involved and shocks you rigid. It's not quite as startling as Elijah Wood's demise in Sin City but because it's mired in a reality we recognise as close to our own as cinema gets, the shock is palpable. Damon is now lured back as the wannabe Emir's future proofing advisor much to his wife's chagrin.

What develops from these highly effective roots is a complex movie that moves at its own pace - some might say slow and I can accept that but then slow suits some movies and told any faster, the message would be pruned back, the power diminished. All power to both Gaghan and Clooney for making a film about as palatable as it can be to those who need to see it, to understand it, to make change happen. Somehow, I doubt that mere movies can alter any ongoing fundamental political practices but it would be a real success if Syriana managed to skew one American mind to the idea that its bush needs pruning. When all narrative threads are knotted together, there is a cathartic release that imprints the movie's dominant central theme on the audience. It's not pretty. It may be true but even if it isn't, it feels like it should be.

Syriana opens in UK cinemas on 3rd March 2006.