KEY POINTS:
On the assumption that President Barack Obama survives for a full four-year term - for it is generally assumed that, as the first African-American President, he will face a higher than average risk of assassination - what changes will he bring to the United States and the world?
It is remarkably difficult to say, for no President since Lyndon Johnson has come to office with so few commitments to specific policies. Oh, all right then, since Gerald Ford - but neither of those men was actually elected to the presidency.
It is now a near certainty that Obama will be the next US President. The media will try to maintain the illusion of a race for the Democratic nomination until Senator Hillary Clinton finally quits (which may not be until the August convention), because it helps to fill the awful gap between the 24-hour news cycle and the actual amount of news available.
But as leading independent pollster John Zogby put it on Wednesday, "To all intents and purposes the race for the Democratic nomination is over."
After last Tuesday's North Carolina and Indiana primaries, there is no mathematical chance for Hillary Clinton to win a majority of the delegates to the Democratic convention, and the flow of money for her campaign is already drying up. It is unimaginable that the so-called "superdelegates" (senior party figures who get an automatic vote at the convention) would naysay the primaries by opting for Clinton, so the case is closed.
Having seen off the Hard Man of the Democratic Party, Obama must now defeat the Hard Man of the Republican Party in November. (Clinton promised to "obliterate" Iran if it attacks Israel; Senator John McCain has proposed threatening North Korea with "extinction".) But it will be hard for Obama to lose while the US plunges into recession and the Republican candidate is still shackled to the Bush Administration's war in Iraq.
About the only thing that would give McCain a chance is a big terrorist attack on the US that drives voters into the arms of those who promise security through endless war. Al-Qaeda would be happy to oblige, for the presence of US troops in Iraq is its best recruiting tool and McCain reckons he would be willing for US troops to stay for 100 years. But al-Qaeda in its current state probably lacks the resources for such an ambitious project. So Obama gets the presidency - and then what? A longish honeymoon, in all probability, while Americans congratulate themselves on having transcended the racist legacy of their past, which means Obama will have a better chance than most new Presidents to change the way things work. And he can probably count on Democratic majorities in both houses of Congress.
On the other hand, he will inherit a ravaged economy and a lost war, so he has little room for expensive domestic reforms or dramatic initiatives abroad. Getting American troops out of Iraq will take several years and use up a lot of his political credit at home, even if it does wonders for America's reputation in the rest of the world.
And he will not be able to cut bloated US military spending at the same time, so there is no early "peace bonus" waiting for him on the fiscal front. Indeed, there is little that any American President can do about a recession in the short run except to wait it out.
Like Bill Clinton before him, Obama will ultimately have the job of repairing the huge budget deficit bequeathed to him by his Republican predecessor, but the only step he can take in the short run is to roll back the huge Bush tax cuts for the rich. So what else can the Democrats do in the meantime that doesn't cost too much?
Reversing the Bush Administration's assault on the constitutional rights of American citizens and the human rights of non-Americans - closing Guantanamo, ending official support for torture, and restoring the civil liberties destroyed by the Patriot Act and subsequent laws - are high-priority tasks that are practically cost-free.
And creating a genuine national healthcare programme would not cost that much in the early years, provided you break the stranglehold of the insurance companies at the same time.
Barack Obama has said very little about this during his campaign (and Hillary Clinton, haunted by her failure to reform healthcare in her husband's first term as President, has said even less). But the fact that about one-sixth of the American population has no access to high-quality medical care is an astonishing failure in a rich democracy, and Obama has travelled enough to see it for the scandal that it is.
Obama may be unconvincing as a gun-loving, truck-driving, fast-food-addicted son of toil, but he is the candidate of the American poor even if many of the white poor don't recognise him as such.
No single reform would do so much to improve the lives of poor Americans as a fully comprehensive healthcare system that is free at the point of delivery.
He has given us few clues about his intentions, but my money says that that will be his first priority in domestic affairs. He might even succeed.
* Gwynne Dyer is a London independent journalist whose articles are published in 45 countries.
