A respected educationalist once told me that the only piece of educational theory which stands the test of time and circumstance is that children respond to the expectations made of them. Tell a child that it is brilliant and he or she will perform well. Infer that it is a failure and he or she will prove you right.

The same is true of international politics, and rather more lethally so.

Take the following scenario: a strategically placed country of almost seventy million people overthrows a right wing dictator. His replacement turns out to be a religious fundamentalist who urges demonstrations against American and Israeli influence. Thus encouraged, radical students force their way into the American Embassy and take sixty-six hostages who are held for almost eighteen months. So far, so bad. This country is then invaded by its neighbour with whom it fights a disastrous eight year long war.

It staggers on for a further eight years under repressive regimes until, with a new constitution, presidential elections are held. Wonder of wonders, a progressive former cleric is elected and begins carefully - so as not to provoke the powerful religious leaders - to bring in much needed reforms. These are popular, particularly with women and young people, so much so that, after four years, he is re-elected with 78% of the vote. The next candidate polled a mere 16%.

Six months later President Bush brackets this country - Iran, as if you hadn't already guessed - with Iraq and North Korea as part of an "axis of evil," and threatens retribution.

The result? The ayatollahs cease to tolerate progressive policies, prevent reformist candidates standing in elections and Iran begins to revert to its former belligerent and extremist self. In short, it begins to act as if it were part of an "axis of evil." The American headmaster tells the fractious child that it is evil, and it slowly but surely becomes so.

As the leader of Dale Carnegie's adopted country, you might have supposed that President Bush would realise that his attack was hardly calculated to win friends and influence people. Or, to move the analogy to Europe, he shows a disturbing affinity to the restored Bourbon rulers of France who had "learned nothing, and forgotten nothing."

All this is not merely academic, nor even tragic; it is downright dangerous. With one speech Bush set Iran's cultural modernisation back twenty-five years. Last year, amidst significant abstentions, Iran elected a hard line conservative, Mahmoud Ahmadinejad, as president - a man with a flair for inflammatory anti-semitic statements.

During his eight years as president Mohamed Khatami needed friends around the world not enemies. He had plenty of the latter amongst the religious coterie that had the last word constitutionally through the Council of Guardians. Khatami showed himself to be a remarkable politician in his skill in gauging the maximum pace of reform that would avoid the wrath from on high. He brought in the rule of law and instituted democratic local government. He encouraged a pluralistic society and, in Tehran at least, women who did not wish to wear the veil went around bareheaded - a remarkable transformation in a Shi'ite islamic state.

One could have expected at least a gentle round of applause from Europe and North America, coupled with practical measures, such as cultural exchanges, assistance with technology, help with what we now apparently call "governance issues" and ministerial visits. The sort of careful programme that would have encouraged Iran without embarrassing President Khatami.

Instead he got slapped down by George W Bush, who had the effrontery to add that "an unelected few repress the Iranian people's hope for freedom." That from a man who had been elected by the Supreme Court about a country whose leader who had polled over three quarters of the popular vote.

Inevitably Bush's accusation was self-fulfilling. The mullahs were able reassert themselves and, with the reformers disillusioned and in disarray, they were now powerful enough to ban most of the reform candidates at the February 2004 parliamentary elections. Iran's developing reform movement was reversed, and all thanks to the foolish remarks of an American president whose incoherence and, frankly, malign influence makes him alarmingly dangerous.

Now, in Mahmoud Ahmadinejad, Iran has a hard line conservative as president who trots out all the traditional anti western and anti-semitic nonsense. Words would be bad enough, but it appears clear that Iran is rapidly developing a nuclear weapon capacity. One scientific source reckons that it is only about three years away. Last November a defence pact was signed with Syria. It is hardly surprising. Iran can see how its western neighbour, Iraq, which doesn't have nuclear weapons, was invaded and occupied by American forces and their allies, whereas North Korea, which does have the bomb, was left well alone.

In politics as in physics, Newton's Third Law operates: for every action there is an equal and opposite reaction. The more the US government threatens, the more the Iranians build their defences. Either the Bush administration simply doesn't understand the character of its self-generated enemies, or it is guilty of breathtaking cynicism in preparing for another war.

Every time Donald Rumsfield or Condoleezza Rice utter the mantra, "we have no plans for military action but it cannot finally be ruled out," it has two effects. First, it strengthens the resolve of the Iranian government to create an ever more formidable defence capability, but, second, it develops the acceptance of the American people for another war. The combination of the two is lethal.

If the Bush administration conceives that Iran is going to be frightened by threats into abandoning whatever nuclear capacity it is engaged in, then its members are alarmingly naive. Unlike Iraq in Kuwait, Iran is not a country that fought and lost an attempt to invade a neighbour and on which a UN inspection regime can be forced. Nor, also unlike Iraq, is it an artificially, and recently, constructed country with powerful ethnic groups that prevent national unity. Iran has almost three times the population of Iraq and, though ethnically diverse, it has a deeply held and over-riding Iranian identity. It would take a peculiar madness to launch military action against Iran.

As the USA continues to show signs of this incipient insanity it is up to Europe to prevent the slide into disaster. European countries, with their deep historical perspective and their experience of war on their own territory, need to take the opposite path and to build peaceful contacts with the Iranian government and to develop positive links with the Iranian people. This will require political strength to stand up to Bush, and, alas, Tony Blair is not going to do it. In this sense the American border is the English Channel.

As I have found working in countries across the world, it is a pervasive error on the part of western people to regard themselves as sophisticated and the rest of the world as backward. I was in Yemen at the time of Bush's first election and the chairman of its electoral commission was appalled at the blatant electoral abuses. He told me that he had written to the American ambassador in Sana'a, offering his help with the electoral process in Florida. Iranians see the television and read the papers.

Iran has the same mixture of human beings as any western country. Its people have the same desires for themselves and their families. Its reform movement was forced into reverse, but it is still there, latent and just below the surface. It is these people who are the solution to the current crisis. Having once tasted freedom, the Iranian people, particularly its women and its youth, will not abandon hope. And it is this hope that needs to be fostered rather than being stifled. The UN Security Council is not the place to change direction. That will have to come from Europe and not from New York - or Washington.

9 February 2006