Less than halfway through Oliver Stone’s W., it suddenly hits you – this isn’t a hatchet job. Contrary to all expectations and media hype, some of it generated by the film-makers themselves, this portrait of George W. Bush by the Hollywood provocateur is not a polemical rant against the man, nor a satirical attack on his presidency.

Instead, over 131 minutes, and through the combined talents of Stone, the screen-writer Stanley Weiser (Wall Street) and the actor Josh Brolin, we are presented with Bush the dreamer, Bush the charmer, Bush the frat boy, Bush the harried son (his relationship with James Cromwell’s Bush Sr forms the dramatic core of the film), Bush the husband, Bush the beleaguered president (his Cabinet is a truly terrifying vipers’ nest), and Bush the lonely, lost man.

Never once do we get a juicy pot-shot at Bush the cartoon villain. Indeed it’s a testament to the movie’s ambitions that Stone manages to transform the now infamous Bush gaffe of the epic press conference pause (as he contemplates his mistakes in office) into a moment of extreme sympathy for his embattled protagonist. If you didn’t know any better, you might think Stone had fallen for his hero.

The director, of course, has been accused of doing just that, and of being over concerned with creating a nonpartisan portrait of Bush. Stone, in return, has been forced into the bizarre situation of defending himself for being fair on Bush. “I have said repeatedly that I’ve tried to be fair and balanced and compassionate above all, about this subject matter,” he said recently. And yet the real surprise here is not that Stone’s W. has been too fair on Bush, and too keen to find the man beneath the monster, but that anyone with a passing interest in cinema might have expected it to be otherwise.

For Stone’s movie is nothing less than the modern political biopic par excellence, a film that grabs its notorious subject matter by the throat and, instead of throttling it, as the world expects, simply looks deeply into its eyes. Frank Langella’s President Richard Nixon, in the forthcoming Frost/Nixon, is irascible, yes, and occasionally terrifying, but he is also witty, droll, and hyper-intelligent in what is a hugely sympathetic portrait of a man tragically undone by his own ambitions. By the closing shot of that movie, of Nixon in noble silhouette, staring into the setting Californian sun, his rehabilitation as a statesman is utterly complete.

Or what about Idi Amin in The Last King of Scotland? The Ugandan dictator’s propensity for mass murder and homicidal mania was duly leavened by a script that rooted his flaws in the abuse he suffered at the hands of colonising British forces, and by a mesmerising Oscar-winning performance from Forest Whitaker.

Even the biggest political bogeyman of them all, Adolf Hitler, got a fair showing in Downfall. Played by Bruno Ganz, he was depicted as someone with occasional flashes of searing insight, but whose mania was exacerbated by the advance of Russian troops.

The problem for polemicists is that the movies are increasingly ignoring any responsibility to address the political issues surrounding the politicians. Instead, modern film-makers, aware of the complexities of contemporary political life combined with the dramatic limitations of partisan character assassination (the Kim Jong Il portrait in Team America: World Police was wildly funny, but it wouldn’t sustain an entire movie) are appealing solely to the limits of Aristotelian drama. “I am trying not to take sides, and to be my political self,” Stone said recently when discussing W. “I feel like I am a dramatist. This is what I do professionally, and I try to keep it as a craft.”

Of course, it wasn’t always thus. In the past, political biopics, from Hollywood especially, tended to be extremely reverential, and concerned neither with politics nor with humanity but with finding the godhead within the man. The five-time Oscar winner Wilson (1944), a saintly portrayal of President Woodrow Wilson (played by the Canadian actor Alexander Knox) was a prime example of unfettered hagiography. Similarly John Ford’s Young Mr Lincoln (1939) created a fictional, equally righteous life for the prepresidential Abraham Lincoln, this time as a crusading attorney. Charlton Heston was suitably ennobled as the seventh American president, Andrew Jackson, in the 1953 biopic The President’s Lady.

At the same time, in Russia, film-makers dared not even depict any recent politicos on film for fear of the state’s reaction – even Sergei Eisenstein’s Ivan the Terrible was banned by Stalin because its uncomfortable portrait of Ivan as an unstable tyrant was felt to have echoes in Stalin’s leadership style. Hampered, it seemed, by the rectitude of the day into a certain stance of presidential awe, Hollywood film-makers were eventually liberated by the chance to depict flawed fictional presidents rather than saintly real ones. Here Peter Sellers’ President Merkin Muffley in Dr Strangelove signalled a gloves-off approach to White House creations.

Subsequently, in everything from The American President to Dave and the TV series The West Wing, the White House assumed the responsibility of not just a glamorous dramatic setting, but the locus of public hopes and fears for what a president might actually be, or could become. It’s hardly surprising, then, that a decade before Barack Obama’s campaign began, Mimi Leder’s Deep Impact had already placed an African American in the White House, in the form of Morgan Freeman’s President Tom Beck. Or that, during the Clinton presidency, Clint Eastwood would give us a duplicitous womanising commander-in-chief in Gene Hackman’s President Allen Richmond in Absolute Power.

Around the world, of course, these same tensions have existed in portraying leaders. Greta Garbo as Sweden’s Queen Christina, Kirsten Dunst as Marie Antoinette, and even Michele Placido as Silvio Berlusconi in Nanni Moretti’s recent The Caiman have been adored or decried in equal measure– either for doing Hollywood hagiography (Marie Antoinette) or being too irreverent (The Caiman).

In Britain, apart from a cottage industry in Churchill movie portrayals (from The Finest Hours to Young Winston to Churchill: The Hollywood Years), the small screen has tended to swallow up most political profiles. However, there have been recent hints that the W.-style humanism is being applied to subjects that would normally be hugely divisive. In Stephen Frears’s The Queen, Tony Blair (Michael Sheen) emerges as a noble hero. On television Margaret Thatcher has already appeared in greatly sympathetic guise, thanks to the actress Andrea Riseborough and the writer Tony Saint, in The Long Walk to Finchley. She is back again, played by Lindsay Duncan, in next year’s very W.-sounding Margaret. The drama will examine her fall from grace (with, one suspects, more than a smidgeon of sympathy).

Nonetheless, the question of how long audiences will tolerate the appeal to humanism rather than to base political urges remains a tricky one. Certainly the sense that the very real villains of our time are being exonerated onscreen is not an easy sell to those directly affected by actions such as war and financial mismanagement. And yet the great attraction in Stone’s film, and the allure of his George W. Bush, is in the idea that he’s just like us, not worse, and certainly not better – and that, given the right circumstances, we might do the same things as he did. We might, in other words, be Bush.

W. is the Times Gala at the London Fillm Festival tonight (Odeon Leicester Square, 7.30pm). It will also be shown tomorrow (Odeon West End 2, 1pm). It goes on general release on Nov 7 2008

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