For most ordinary Americans, those not encumbered with an expensive education or infected by prolonged exposure to cosmopolitan heterodoxy, patriotism is a consequence of birth.

Their chests swell with pride every time they hear the national anthem at sporting events. They fill up with understandable emotion whenever they see a report on television about the tragic heroics of some soldier or Marine who gave his life in Iraq or Afghanistan.

Foreigners don't have to like America - and they've certainly exercised that freedom in the past few years. But most Americans can distinguish between the transience of policy failure and the permanence of the national ideal.

And surely even critics of the US could scarcely deny that there have been real causes for American pride in the past 25 years: the fall of the Berlin Wall; the victory in the first Gulf War in 1991; the nation's unity in grief and resolve after September 11. Heck, I suspect most Americans got a small buzz of patriotic pride this week when they heard that one of their multimillion-dollar missiles had shot a dead but dangerous satellite travelling at 17,000 miles per hour out of the sky so that it fell harmlessly to Earth.

A race like a crackpot Dynasty

The contest between Barack Obama and Hillary Clinton matches any fiction

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BACKGROUND

• The ascent of Barack Obama, Mr Charisma

• Decay, jobs and guns fall under the spotlight

• Free trade: Clinton/Obama's mistakes

But not, apparently, Michelle Obama, wife of the man who is now the putative Democratic candidate for US president, and at this point favourite to succeed to that job. In what might be the most revealing statement made by any political figure so far in this campaign season, Mrs Obama caused a stir this week. She said that the success of her husband Barack's campaign had marked the first time in her adult life that she had felt pride in her country.

This, even by the astonishingly self-absorbed standards of politicians and their families, is a remarkably narrow view of what makes a country great. And though she later half-heartedly tried to retract the remark it was a statement pregnant with meaning for the presidential election campaign.

Now, to be fair to Mrs Obama, she would surely have a point if she had said that it was a source of incomparable pride to her and all African-Americans that in a country with a long and baleful history of racial discrimination, one of their own was within serious range of becoming president. All but the most irredeemably racist Americans would surely agree with that.

But that was not what she said. She said this was the only time in her adult life that she had felt pride in America.

It was instructive for two reasons. First, it reinforced the growing sense of unease that even some Obama supporters have felt about the increasingly messianic nature of the candidate's campaign. There's always been a Second Coming quality about Mr Obama's rhetoric. The claim that his electoral successes in places like Nebraska and Wisconsin might transcend all that America has achieved in its history can only add to that worry.

Secondly, and more importantly, I suspect it reveals much about what the Obama family really thinks about the kind of nation that America is. Mrs Obama is surely not alone in thinking not very much about what America has been or done in the past quarter century or more. In fact, it is a trope of the left wing of the Democratic party that America has been a pretty wretched sort of place.

There is a caste of left-wing Americans who wish essentially and in all honesty that their country was much more like France. They wish it had much higher levels of taxation and government intervention, that it had much higher levels of welfare, that it did not have such a “militaristic” approach to foreign policy. Above all, that its national goals were dictated, not by the dreadful halfwits who inhabit godforsaken places like Kansas and Mississippi, but by the counsels of the United Nations.

Though Mr Obama has done a good job, as all recent serious Democrats have done, of emphasising his belief in American virtues, his record and his programme suggest he is firmly in line with this wing of his party.

This, I think, not his inexperience in public office, is the principal threat to Mr Obama's campaign. His increasingly desperate opponent, Hillary Clinton, keeps hammering away that his message is all talk and no substance - and she was joined this week by Mr Obama's likely Republican opponent in the November general election, John McCain.

But if you listen to Mr Obama's speeches, it is not the lack of substance but the quality of it that ought to worry Americans. His victory speech after his latest primary win in Wisconsin this week was a case in point.

There was no shortage of proposals. He plans large increases in government spending on health and education. He wants to tax the rich more to pay for it. He is against companies using the opportunities of free markets to restructure their operations in the US. He is vehemently protectionist. He continues to insist, despite the growing evidence that this left-wing nostrum would be lunacy, that the US must pull its troops out of Iraq with the utmost dispatch.

While he speaks of the need for Americans to move beyond partisanship (“We are not blue states or red states, but the United States” is a campaign meme), when you cut through the verbiage there is nothing to suggest he believes anything that is seriously at odds with the far Left of his party. If you think about it for a second, it's not really an accident that he has been endorsed by the likes of Ted Kennedy and Jesse Jackson.

Though he talks with great eloquence about the future, he sounds for all the world like one of the long line of Democrats from George McGovern to Walter Mondale to Michael Dukakis, who became history by espousing policies and striking a rhetorical pose that was well out of the mainstream of American politics.

America is certainly moving left in the post-George Bush era. The long period of conservative ascendancy is clearly over, buried by a Republican Party of recent years that has preached intolerance and practised incompetence. That a new era in American politics is beginning is not in doubt. But are Americans really ready to leap all the way across in one go to embrace a European-style Left?

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