Katherine Butler: Iranians are humans, you know

Here's a story. Urban-dwelling middle class couple, one bright school-age daughter. Nice apartment, good part of town. Husband and wife juggle the demands of their respective careers and the twice-daily school run with the obligations of extended family (the husband's Alzheimer's-afflicted father is living with them). But the marriage is unravelling.

She wants to relocate – abroad – he doesn't. She moves out, they hire a home-helper for the old man – a poor working-class woman from the sticks. Bad things happen and a tricky situation becomes despairingly awful for all concerned. And this compelling human tragedy of truth and lies and communication breakdown plays out where? North London? Paris? The Upper West Side of New York ? Tel Aviv?

The fictional action I'm describing is the plot of A Separation, the remarkable film that won the Oscar on Sunday in the Best Foreign Language category. Its setting is Tehran.

The big question prompted by the award – the first ever Oscar for an Iranian film – is this: could the box-office succeed where sanctions have failed? Could Oscars diplomacy deliver us from the military confrontation over Iran's nuclear programme that Israel seems to want and which the British Government has joined in threatening?

It would be naive to imagine President Ahmadinejad, charmed by the Hollywood prize, suddenly announcing he will comply with the West's demands. Some factions in Iran may even choose to see A Separation's validation by the American movie industry as a provocation. Independent film-makers in Iran seen as too beloved of the West have been jailed. My guess is that the film's success will delight ordinary Iranians but be officially ignored – with any luck director Asghar Farhadi will be left to pursue his craft in peace.

The film could however – and in a much more subversive way – influence the course of history, assuming that thanks to this Oscar, more people in Europe, America and Israel end up going to see it. Indeed, in my view, only when you have watched this painful film should you be permitted to have an opinion on how useful, sane or morally acceptable it is to even discuss bombing Iran rather than seeking a diplomatic end to the over-hyped stand-off about its desire for a nuclear capability.

Farhadi's drama has nothing overt to say about regime change, nuclear weapons or revolutionary Islam, although the catalyst for the couple's divorce is the wife's desire to leave the country so that her daughter can be educated abroad. But its focus on the everyday and on contemporary human problems is its power. It is a portrait of a disintegrating relationship against a backdrop of family obligation and social division, and everyone worries about paying the bills. It could easily be transposed to a US setting, in which you could imagine the lead characters being played by George Clooney or Julianne Moore.

The comments yesterday of Israelis who saw A Separation and told an AP reporter they were surprised that Iranians had fridges and washing machines were saddening, and revealing. But hardly surprising when you think about how Iran and Iranians are generally characterised in Western discourse. Our mental images of the country involve fearsome black-clad women or angry men chanting "Death to America". Words like "mullahs" (you barely need the prefix "mad" any more), "hardliners" and "threat" are usually linked in the same sentence. A news report about Iran not containing the words "nuclear ambitions", "nuclear scientists" and "terror" – seems unimaginable.

Iran has become more of a concept, a frightening idea, than a set of people with a proud civilisation, a turbulent modern history and a legitimate viewpoint or even humanity. And of course you can only convince yourself that it is morally legitimate to bomb other people – don't kid ourselves that Iran's nuclear sites could be destroyed without also bombing a great many Iranian women, men and children – when you have dehumanised them or reduced them to caricatures of evil. The enemy.

Iran's isolation in the world since 1979 is what sustains the rule there of a repressive elite motivated as much by money, and its own survival, as theocratic ideals. But after 30 years of mutual suspicion it has become difficult for most Westerners to think of Iranians en masse as anything other than terrifying, irrational freaks on a martyrdom mission, when there is a daily and hypocritical drumbeat led by Fox News neo-cons about the supposed threat they pose.

The characters in A Separation wear RayBans, drive Peugeots and are caught up in the daily drama of their own lives, not in wanting to wipe anyone off the map. Unlike the dangerously lazy narrative that is now received wisdom about Iran, the film is complex, sophisticated and nuanced. If even some of the cinema-going public come away thinking of Iranians as ordinary people like themselves, perhaps the sleepwalk to a futile war might become a little less inevitable than it now looks.