It's funny how the harder you look at something, the harder it can be to understand it. I can't recall a US presidential election that has attracted more attention. But neither can there have been a time when the world has watched what goes on in America with the nonplussed, horrified incomprehension it has now.

Travelling in Britain this week, I've been asked repeatedly by close followers of US politics if it can really be true that Barack Obama might not win. Thoughtful people cannot get their head around the idea that Mr Obama, exciting new pilot of change, supported by Joseph Biden, experienced navigator of the swamplands of Washington politics, could possibly be defeated.

They look upon John McCain and Sarah Palin and see something out of hag-ridden history: the wizened old warrior, obsessed with finding enemies in every corner of the globe, marching in lockstep with the crackpot, mooseburger-chomping mother from the wilds of Alaska, rifle in one hand, Bible in the other, smiting caribou and conventional science as she goes.

Two patronising explanations are adduced to explain why Americans are going wrong. The first is racism. I've dealt with this before and it has acquired no more merit. White supremacists haven't been big on Democratic candidates, whatever their colour, for a long time, and Mr Obama's race is as likely to generate enthusiasm among blacks and young voters as it is hostility among racists.

In a similarly condescending account, those foolish saps are being conned into voting for Mr McCain because they like his running-mate. Her hockey-mom charm and storybook career appeals to their worst instincts. The race is boiling down to a beauty contest in which a former beauty queen is stealing the show. Believe this if it helps you come to terms with the possibility of a Democratic defeat. But there really are better explanations.

One is a simple political-cultural one. This election is a struggle between the followers of American exceptionalism and the supporters of global universalism. Democrats are more eager than ever to align the US with the rest of the Western world, especially Europe. This is true not just in terms of a commitment to multilateral diplomacy that would restore the United Nations to its rightful place as arbiter of international justice. It is also reflected in the type of place they'd like America to be - a country with higher taxes, more business regulation, a much larger welfare safety net and universal health insurance. The Republicans, who still believe America should follow the beat of its own drum, are pretty much against all of that.

You can argue the merits of each case. But let me try to explain to my fellow non-Americans why Mr Obama's problems go well beyond that. Even if you think that Americans should want to turn their country into a European-style system, there is a perfectly good reason that you might have grave doubts about Mr Obama.

The essential problem coming to light is a profound disconnect between the Barack Obama of the candidate's speeches, and the Barack Obama who has actually been in politics for the past decade or so.

Speechmaker Obama has built his campaign on the promise of reform, the need to change the culture of American political life, to take on the special interests that undermine government's effectiveness and erode trust in the system itself,

Politician Obama rose through a Chicago machine that is notoriously the most corrupt in the country. As David Freddoso writes in a brilliantly cogent and measured book, The Case Against Barack Obama, the angel of deliverance from the old politics functioned like an old-time Democratic pol in Illinois. He refused repeatedly to side with those lonely voices that sought to challenge the old corrupt ways of the ruling party.

Speechmaker Obama talks about an era of bipartisanship, He speaks powerfully about the destructive politics of red and blue states.

Politician Obama has toed his party's line more reliably than almost any other Democrat in US politics. He has a near-perfect record of voting with his side. He has the most solidly left-wing voting history in the Senate. His one act of bipartisanship, a transparency bill co-sponsored with a Republican senator, was backed by everybody on both sides of the aisle. He has never challenged his party's line on any issue of substance.

Speechmaker Obama talks a lot about finding ways to move beyond the bloody battlegrounds of the “culture wars” in America; the urgent need to establish consensus on the emotive issue of abortion.

Politician Obama's support for abortion rights is the most extreme of any Democratic senator. In the Illinois legislature he refused to join Democrats and Republicans in supporting a Bill that would require doctors to provide medical care for babies who survived abortions. No one in the Senate - not the arch feminist Hillary Clinton nor the superliberal Edward Kennedy - opposed this same humane measure.

Here's the real problem with Mr Obama: the jarring gap between his promises of change and his status quo performance. There are just too many contradictions between the eloquent poetry of the man's stirring rhetoric and the dull, familiar prose of his political record.

It's been remarked that the biggest difference between Americans and Europeans is religion: ignorant Americans cling to faith; enlightened Europeans long ago embraced the liberating power of reason. Yet here's an odd thing about this election. Europeans are asking Americans to take a leap of faith, to break the chains of empiricism and embrace the possibility of the imagination.

The fact is that a vote for Mr Obama demands uncritical subservience to the irrational, anti-empirical proposition that the past holds no clues about the future, that promise is wholly detached from experience. The second-greatest story ever told, perhaps.

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