The one thing known by all three candidates for the presidency is that whoever wins must do something painful. He or she must negotiate the terms of an eventual retreat from Iraq, not with the Iraqis but with the Americans. Even John McCain, who watched the retreat from Vietnam and swears he will “stay a hundred years in Iraq until peace, stability and democracy” are achieved, will eventually leave, if only under the lash of Congress.

Yet now is not the time to admit it. A war that is unpopular with 60-70 per cent of Americans is not politically sustainable, however stupefying the cost. But the modalities of its ending are unpredictable and possibly humiliating. Both Hillary Clinton and Barack Obama may call for early withdrawal, at least of “combat troops”. But the real paradox of Iraq is that McCain knows he must find a way of leaving, and Clinton and Obama know they must find a way of staying, if only for the time being. Though foreign policy is rarely salient in peacetime elections, Americans have been almost persuaded by their president, George Bush that they are not at peace.

Americans still do not travel abroad, and rely on television news for their knowledge of foreign places, which they continue to regard with bizarre suspicion. Hence a world view is lumped in with defence and security in a collective paranoia. And a candidate’s stance on foreign policy is a proxy for his or her character. To this the candidates must pander. Hence Clinton emphasises her “role” in Kosovo and her “mis-remembered” landing in Bosnia under fire. Obama stresses his links to three world continents and a seminal visit as a young man to Karachi. McCain trumps them by having been tortured by the Vietnamese, a sanctification whose only drawback is that it recalls his age (71). All must appear trigger happy.

McCain may distance himself from the unilateralism of George Bush and remark that Americans must show “a decent respect for the opinions of mankind”. But his team is penetrated by such neocons as Robert Kagan and John Bolton, on the basis that “if we can’t beat him, we can persuade him”. The only thing to be said with confidence about McCain is that his position on everything is uncertain. Desperate not to be outflanked on defence, Clinton said yesterday that she would “totally obliterate” Iran if Iran bombed Israel. Last week she offered an astonishing nuclear-shield guarantee for neighbours of a nuclear Tehran. Obama duly chided her as “Annie Oakley with a gun”. Yet he has tended to follow her positions with a ready me-tooism, as on Tibet.

Enthusiasts for Obama, more plentiful beyond America’s shores than within them, regard him as the most plausible candidate to pilot America to a new and more internationalist haven than this. His weakness is that he seems unknown, not quite American, exotic, elitist, intelligent. Were Obama to emerge from this week’s still uncertain events as the Democratic candidate, the smart money in Washington is still on McCain to win a dirty election. At a distance I continue to find Obama one of the most exciting and potentially able men to run for the American presidency in a generation. His capacity to transform America’s self-image and world image is colossal. But to do so he must confront America’s atavistic love affair with

war, and that will be hard. — The Guardian