W.: a man who changed the US for good or for bad I Has Oliver Stone fallen for Dubya?

Oliver Stone’s portrait of George W. Bush is not destined to hang over the family fireplace in Southfork any time soon. Not because it’s a ghastly likeness, but because W., the Times Gala at the London Film Festival, is achingly true. The sheer warmth of Josh Brolin’s performance as W is as unexpected as Stone’s restraint.

The film is also witheringly funny. There’s a priceless scene in which the President and his overdressed chiefs of staff get lost when they take a wrong turn on his ranch. Brolin’s W might be an idealistic cowboy who is out of his depth when it comes to policy, but he is decidedly human in a crisis. The result is almost guilty sympathy for the 43rd President of the United States.

Stone wrong-foots every critic who assumed that he would lay into the Bush legacy like a wrecking ball. He does, of course, but it’s the most half-hearted of swings. The pleasure of Stanley Weiser’s script is that it is far more curious about Bush’s character, rather than his career.

The film begins in 2002 with the “axis of evil” speech, and ends in 2004 when Bush starts losing control of the war in Iraq. We wince as Brolin’s Commander-in-Chief, and his inner circle, collude over ruinous choices. The film is almost carelessly entertaining about loaded foreign policy decisions that stretch back to Bush Senior’s time in office.

The Machiavellian contest about who actually pulls the strings is where the film begins. There’s an almost Kubrick sense of lunacy about Richard Dreyfuss’s fabulously unscrupulous Dick Cheney. The ease with which Dreyfuss slides policy decisions about "waterboarding " past George as he absent-mindedly tucks into a large cheeseburger and freedom fries in the Oval Office is pure comic art. The cabinet meeting where Cheney unfurls an oil map of the world with Iran as the untapped must-have prize is just plain frightening. Scott Glenn’s Donald "Rummy" Rumsfeld can only stew and admire. And Toby Jones makes up the unholy trinity as Dubya’s poisonous political mentor, Karl Rove. These venal hawks are so deliciously two-dimensional that they look as if they’ve been steam-pressed for the occasion.

Thandie Newton parrots the party line as the chief cabinet cheerleader, Condoleezza Rice. Only Jeffrey Wright offers any sensible resistance to the war games as General Colin Powell. But these characters are all grist to Stone’s mill. It’s the President’s juicy flashbacks to his past that make this modern morality play such a spiky pleasure.

The back story is a classic rake’s progress from spoilt Yale student to spoilt shiftless bum. James Cromwell’s George Bush Sr is forever bailing his alcoholic son out of bar-room bust-ups and local scandals. George W. can’t hold down a job for ten minutes. He can’t hack the raw end of the oil business. He can’t manage the glamour of a baseball club. His parents think he’s joking when he decides to run for the governorship of Texas. Meanwhile W. fumes and wails about the attention they lavish on his younger and more talented brother, Jeb (Jason Ritter). “You’re a disappointment to me Junior” is a phrase that echoes throughout the film.

Ultimately, W. is great soap and awful pop psychology. But against all the odds, it makes perfect sense. George W’s epiphany when he wakes up from a coma, kicks the bottle, and discovers God transforms his life. It also gives him a truly unnerving belief in his own anointed destiny. The President wears his evangelical faith like armour. It hides a man shredded by anxiety.

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