Speeches matter. Barack Obama’s oration to the Democratic convention on Thursday was an epic performance. He held 80,000 people in his hand. He made them laugh and he made them cry. He was humble and he was grand. He thanked the right people, especially Hillary Clinton, and in the right order.

Churchill, even in despair, knew he could give the nation a fillip with a speech. Kennedy agonised over his speeches. The last address by Martin Luther King was the essence of his fame. Politics is the art of communicating intimacy to a crowd. No television chat show can match the rhetoric of a Cicero, a Henry V, a Wesley or a Gladstone.

Obama’s handling of family, friends, opponents, even God, seemed personal and deft. The cadences, timing and body language were faultless, conveying sympathies of pain, pleasure and, above all, hope. Obama gets the point. He is good at Cicero.

But too good? We know Obama can speak. He can also write. I have read both his books and they, too, are good. His autobiography, Dreams from My Father, written when he was 33, is a masterpiece in the tradition of the American search for identity. The Audacity of Hope, written when he had become a senator, is no less articulate as a study in American politics. On any showing this man has emerged as an intelligent and exciting figure. At the very least it would be intriguing to see how he would perform as president of America and leader of the free world.

At this point a classic American cussedness enters the debate. Whether he should win is confused with whether he can win. The world’s greatest festival of democracy descends into paradox. Is America, the home of black advancement, “ready” to elect a black man? Is Obama too elitist yet too popular, too radical yet too much a trimmer, too Harvard yet too exotic in his poor background? Is he too inexperienced abroad yet too much liked abroad? Is he too slim, too happy? Is he just too . . . everything?

For a man who has had to fight his way against every conceivable disadvantage, this must be hard to take. Black Americans may no longer need to know their place, but they should know their style. It should not embrace a booming self-confidence.

As John McCain this week enters the spotlight, these qualities will be tested yet again, as they were in the bruising fight with Hillary Clinton. McCain’s selection of a conservative beauty star, Sarah Palin, as his running mate somehow balances the Obama charisma with glamour. It certainly balances Obama’s choice of a liberal old-timer, Joe Biden.

It also stamps this presidential contest as emphatically one of opposites. McCain is running as a conservative. The specifics in Obama’s speech – and he was not afraid of them – indicate a politician of traditional Democratic credentials. Obama is for those suffering the recession, for the poor and middling rich and against the corporate America that has lived high on the hog under the Republicans. He is set on healthcare reform, welfare reform and higher rate taxation. He is no great friend of free trade.

Obama may have little executive experience, but neither has his opponent. What can be seen from the campaign is positive: aides protest that he runs a disciplined ship. There has been none of the acrimony and bust-ups that normally consume the primary trail.

Certainly Obama has played the cautious legislator, equivocating over gun control, Iraq and Afghanistan. He has been goaded into showing himself tougher than tough in foreign policy, yet has chosen his words with care. On America’s gaffe-strewn morality agenda, he has been sure-footed.

Of all the accusations against Obama at home that have so puzzled America’s friends abroad, none has seemed more bizarre than that he is popular with them. There is no contest here. In Europe, Gallup recently put Obama on between 50% and 85% support, with McCain in the range of 15%-20%. Across Africa, Asia and Latin America, Obama leads by nine to one. He is by far the most popular world politician in a generation. This surely matters. It is a contest from which the world cannot stand aloof, since American presidents do not stand aloof from the world.

Every American voter casts a de facto proxy vote for the disenfranchised millions who consume America’s foreign and military policy abroad, from Iraq, Afghanistan, Sudan and Burma to benighted Palestine. For tens of thousands of them, an American president is the difference between life and death. Millions more depend on the presidential election as beneficiaries of US aid, or as victims of US hostility and sanctions. Billions of Iranians, Pakistanis, Russians and Chinese have an interest as nations which American governments criticise and threaten. Obama’s global popularity lead over McCain is thus more than a beauty contest. Were he to be elected, his country would unquestionably experience an immediate and dramatic surge in popularity.

In Pakistan recently I was shocked at the antiAmericanism displayed in opinion polls, the media and in conversation. This was not just the result of a decade of US hamfisted military intervention in the region. It also arose from the intervention having fuelled a reaction among Islamist fundamentalists, whom moderate Pakistanis fear as much as do Americans. Such people do not hate the United States; only the stupidity of its governments.

This is the hope that Obama offers the world, of an end to stupidity. His name, his ethnicity and his message of conciliation and negotiation promise a new chapter. Americans, locked in the prison of their media and their aversion to travel, cannot begin to realise how powerful a message would go out in the election of a black president.

This is unrelated to what such an election would mean in practice.

Obama has been forced to back away from an immediate end to the Iraq war and wants, recklessly, to entrap his country further in the unwinnable Taliban insurgency in Afghanistan/Pakistan. He also appears compliant in the insane Nato strategy of encircling Russia with belligerent states.

The truth is that liberal presidents are often forced to be illiberal, doveish ones to be hawkish. Obama would find it hard to appease Palestine, Iran, the Taliban or Moscow. He would find it hard to face down his protectionist supporters in the unions: witness his offer to use federal money to “stop the exporting of American jobs”. He would find it hard to give meaning to “ending American dependence on Middle East oil”.

For all that, no student of this man can doubt his intelligence or his sensitivity to shifts in world opinion. Obama’s account in his memoir of the US legal system as “a nation arguing with its conscience” might also refer to a presidential election. This argument, he believes, should be so conducted that “what binds us together might somehow ultimately prevail”.

This optimistic vision of America might equally refer to the world. After a period when that great nation has made such a mess of trying to rule a unipolar world, Obama offers to clear its decks and start afresh. It is on that opportunity as much as anything within America that its citizens are about to vote.

simon.jenkins@sunday-times.co.uk

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