But even if, as looks increasingly probable, the Illinois Senator reaches the White House, perhaps we should take the opportunity of his British visit to pause for thought.

For while the more intemperate of his supporters seemingly views Barack Obama as a uniquely winning combination of Socrates, Will Smith and Bambi, his foreign policy is assuming a rather stealth-like character. Is Obama the candidate of withdrawal from Iraq, direct negotiations with Iran, and hostility to NAFTA and other free trade agreements? Or is he the candidate of a careful drawdown in Iraq, preparations before any engagement with Tehran, and a commitment to free trade that now rejects protectionism as "overheated" campaign rhetoric?

The reality is that only time will tell us. But there are three reasons why the expectations of profound change in US foreign policy should be tempered.

First, the Bush era was not the unilateralist hell that Obama will repudiate with a multilateral heaven. Yes, Bush invaded Iraq without a second UN resolution, withdrew from some treaties that hampered American interests and had a discomfort with delicate diplomacy. But the Bush administration insisted on six-party talks on North Korea, encouraged the E3 (the UK, France and Germany) to take the lead on tackling Iran's nuclear ambitions, and substantially increased US aid to Africa. American relations with China and India, too, have not been so strong for decades.

Second, if we are to judge him by his general election rhetoric, not the campaign he waged in the Democratic Party primaries, Obama is tacking rapidly and strongly to the basic bipartisan foreign policy consensus in America. Much as he seems to evoke John F. Kennedy rather than Jimmy Carter in his approach, he increasingly resembles a Cold War style Democratic hawk. It is precisely for that reason that the liberal base of the party is beginning to worry more and more about potential buyer's remorse.

Third, for all his eloquence and abilities, certain fundamental features of the foreign policy challenge remain likely to be depressingly intact after January 2009. The UN, for example, is rarely able to muster decisive action on issues from Darfur through Burma to Zimbabwe and Iran.

Its Security Council remains locked in the pattern of the victors of the Second World War, some 63 years ago. Trade talks, from the Doha Round to bilateral deals with Washington, remain stalled. And serious threats from autocratic actors such as Russia and Iran remain underrated by cosmopolitan international opinion. Obama, as he surely knows, will inherit a world stage with some deeply unpleasant actors on it. And his prospects for leading decisive change therefore remain subject to powerful political limits.

Indeed, it is exactly because the global post-Bush sigh of relief will be so profound that the pressure on Obama to deliver is likely to be ridiculously, and unsustainably, high. Already, his advisers are
said to be privately briefing European and other diplomats not to expect a sudden and decisive turnaround in US foreign policy – suggesting instead that there is likely to be more in common between Bush's current term and Obama's first than there was between Bush's first and second terms in office.

What remains worryingly uncertain, however, is just how Obama's inexperience will affect his performance in the Oval Office. While his oratory is often compelling, it has a disturbing tendency to veer to the vapid. Not so much the audacity, but the banality, of hope. And while the Senator prides himself on opposing the war in Iraq in
2002 when he was not then in the Senate, and when John McCain strongly supported it, on the central issue of the last two years – the surge in Iraq – Obama embraced the wrong position, opposing it and siding with the establishment consensus behind the Baker-Hamilton Report.

McCain, by contrast, was a lonely voice endorsing strongly the surge that has finally seen al-Qaida in Iraq routed. We have to hope that Obama has learnt the lesson, but we should maintain a prudent caution as to whether that is indeed the case.

One final factor that complicates political futurology further is often absent from media coverage of this fascinating campaign: Congress.

If the congressional elections of 2008 yield a larger majority for the Democrats in the House of Representatives and the Senate, as they seem likely to do, the "real" Obama may seem even more difficult to identify. On trade policy, especially, the pressures on an Obama White House to embrace the protectionist sentiments of the party's base will be intense. Again, we should hope that Obama resists them, but we should not be surprised if he instead submits.

In sum, then, the continuing reinvention of a young and untested candidate unfolds with compelling plot lines and convoluted interpretations of just what makes Obama tick.

The irony is that while only he really knows that, we will all likely soon find out, for good or ill. Let us hope for the "liberal Reagan". But let us not be too surprised if we instead encounter the black Jimmy Carter.

To order a copy of After Bush: The Case For Continuity in American Foreign Policy from the Yorkshire Post Bookshop, call free on 0800 0153232 or go online at www.yorkshirepost bookshop.co.uk. Postage and packing is £2.75.


Timothy Lynch and Robert Singh are the authors of After Bush: The Case For Continuity in American Foreign Policy published by Cambridge University Press, price £20.