We all know that, so it was no surprise this morning that he pulled out the stops for his acceptance speech in Chicago, re-elected for a second term despite the recession and his own underwhelming record in office, the backdrop to a bitterly partisan campaign against Mitt Romney. I found it more poignant than was probably intended.
In an age where the conversational style of television interviews is the dominant style of public discourse – the glib soundbite, the personal confession, the unconvincing attempts by extraordinary men (if only in the size of their egos) to persuade voters they are just like them – people often mistrust the big speech with its naked appeal to suspend disbelief.
Why? Because the 20th century was littered with such promises, most notoriously in the mid-century heyday of totalitarianism, though it is always worth recalling that Franco, Stalin and Mao were not public speakers in the Hitler or Mussolini mould. Churchill was an old-school rhetorician, but America's FDR, hero of the fight against Depression and war, specialised in the radio "fireside chat".
Both Ronald Reagan and Bill Clinton, folksy exponents of Middle America's virtues, could do both. Tony Blair was pretty good. Margaret Thatcher, like Charles de Gaulle and William Gladstone, addressed all audiences as if they were a public meeting (as Queen Victoria complained of Gladstone), exceptional public figures all of them. Most of the time we have to settle for greater mediocrity.
Was the animating spirit of this morning speech actually Jack Kennedy, whose inaugural State of the Union address in 1961 stirred many listening hearts? The cadences were there, but so were those of Martin Luther King: the preacher's habit of repetition on a rising note which are so familiar to millions of Americans, black and white.
But Kennedy's speech famously focused on the historic tussle with Soviet communism – then nearing its peak – the young, new president's willingness to "pay any price", his challenge to Americans to "ask not what your country can do for you – ask what you can do for your country".
Stirring stuff but, in the America that Obama leads, international affairs take second place to healing domestic wounds and squaring up to the challenge – political, economic, cultural, educational – that comes from a resurgent Asia. Russia, hobbled as usual by a command economy incompetently run, was never the threat that China poses. But China has not been the dominant focus of this election.
Obama's problem has always been that he can hit the high notes of the politician's trade, but not the low ones, the ones that "squares or squashes" his opponents – the phrase is David Lloyd George's, a British reformer who could do both – and persuades voters to follow down necessary roads they may not want to travel. He promises to try harder second time around. Good.
But that comes later. Today was an occasion for the lofty phrase about the bright, if tarnished, promise of America's future and for gestures of conciliation to a defeated opponent and his supporters.
The president struck what Democratic voters – and many conservatives as well as liberals abroad – will find more persuasive notes than Governor Romney might have offered: inclusivity, education, the need to get the US federal budget back into better balance, to protect the weak and hold the ever-more powerful of corporate America to better account.
He mentioned military wives, and the need to ensure that their husbands get civilian jobs on leaving the services, and families struggling to pay the bills for sick children – one in Mentor, Ohio, no less, how suitable for a mentoring president – of the women and Hispanic voters, and the young, who helped to secure his second term.
But he doggedly stuck to the grooves of the American Dream. "You can make it here in America if you're willing to try," he said towards the end. Well, yes, and his own improbable career as America's first Pacific president as well as its first black one shows it can still be done.
But all the data about rising inequality and stalled middle-class incomes, which is a story at least a generation old now, reminds his listeners how hard the dream has become for millions, especially for the poorer whites who – unlike many of the women, blacks and Hispanics in Obama's coalition – have seen their living standards and prospects decline.
With or without the rise of China, this would be a problem. It is the dysfunctional American political system which has gridlocked Washington, raising the prospect of the "fiscal cliff" disaster in a few weeks' time if compromise is not reached. Obama's victory does not guarantee success; far from it. That was the poignancy of this morning's speech for me.
"I have never been more hopeful about America's future," the president said. Well, good luck. Here's hoping he knows something the rest of us can't quite see; even if it is only his own determination to learn from past mistakes and do better.
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image: © Marc Nozell