KEITH DUGGAN SIDELINE CUTThe Games just gone hammered home the truth that modern competitors' concerns do not extend beyond the all-consuming interest in they fare in their own sport

THE WORLD keeps turning. Many people stayed up late on Thursday night to watch Barack Obama addressing the world from the Mile High stadium in Denver. You watched this handsome, skinny black man spinning his wonderful, dreamy narrative of hope and change and you wondered if this will be a face that is beamed into every home on every news channel for the next decade, or if the whole Obama movement would turn out to have been a chimera, a radical political venture that had to, sooner or later, misfire.

The magical thing about huge sports arenas is that, on nights of improbable drama or emotion, the 80,000 people locked inside share in a collective energy that can make literally anything seem possible. It was so at Live Aid. It was so when Ireland hosted the England rugby team at Croke Park. And it was, of course, so in Beijing. But as the latest Democratic Shining Knight stood there with his family and that of Joe Biden, his white running mate, in a cinematic picture of racial harmony, it was hard not to hear the nagging voice that keeps saying this can't happen.

It was hard not to feel that just 50 years after Rosa Parks refused to give up her seat in an Alabama bus and just 40 years after Tommie Smith and John Carlos raised their fists in that deathless, silent protest against black oppression at the Mexico Olympics it is simply too soon - perhaps decades too soon - for the great majority of US citizens to take the great leap forward and put a man of African-American descent into the White House. But what an evening, shimmering with goodwill and optimism! And as the fireworks exploded afterwards, it drew inevitable comparisons with the last globally broadcast stadium show in Beijing.

Already, in the ever-restless world of sport the Beijing Olympics has just vanished from the horizon. There must be an anti-climactic mood on the big city right now, with nothing much to do but get on with the business of ordinary living and smoggy skies and aiding China's march to a place of economic strength that will reflect their unassailable position in the gold-medal tables last week.

Fifty-one Chinese athletes managed gold for the People's Republic and from the tears of relief from those who won and abject disappointment from those who failed, we could only guess as to the quality of the lives they led as they trained and fretted and worked towards the winning that one race or fight or lift or competition.

The suspicions about the age of the Chinese women's gymnastics team will not go away, and now that the Games have ended the criticisms about the State's paranoid fear of protest have grown louder, with general condemnation of the imprisonment of two elderly Chinese women for requesting permission to protest from their government.

In the years and decades to come, it will be no surprise if stories start leaking out about the lengths to which the Chinese athletes went - and were pushed to - in the great collective effort to become the envy of the sporting world. Of course, the vast majority may well believe the pain they endured was worth every second of it. And from the night of the opening ceremony, it became apparent the notion that the Chinese were anxious to impress the world was just Western vanity.

They had no doubt but their show, their Games, would leave everyone, from heads of states to spectators, taken aback and, in some vague way, a little bit frightened by what the scale of the Olympics suggested about the scale and potential of the host country.

The Chinese confidence was such that by the end of the whole extravaganza, they were able to poke fun at the burlesque contribution the British made to the closing ceremony, as they managed to reduce their emblems of Empire to a double-decker bus and an X-Factor winner. They might as well have included Doctor Who emerging from a phone box or Ronnie Corbett doing a vintage sketch.

And how the Chinese must have delighted in the exotic sight of Boris Johnson bumbling forward to accept the Olympic flag; the mayor of the next host city, blond and squiffy and untidy. There was nothing about that acceptance to suggest London can come close to repeating the splendour of the Beijing effort.

China won hands down, softening the global view of its regime, reigning supreme on the medals table and, most importantly, not losing face. As the Olympics days turned over story after story of triumph and heartbreak, the threat of an explicit gesture of protest from any athlete faded.

There was no evidence of the burning spirit of independence and defiance that provoked Smith and Carlos in Mexico in 1968. During the parade of nations, all of the athletes, from the superstars to the most obscure, just looked happy to be there. It all hammered home the truth that modern sport rarely houses competitors whose sense of place and of justice extends beyond an interest in how they fare in their own sport. Smith and Carlos paid dearly for their gesture, ostracised by their sporting committees so much that at one point Smith ended up coaching in provincial England to make a living. His marriage broke down; Carlos's wife succumbed to a suicide that was attributed to the pressure of the infamy heaped upon her husband in the years afterwards. Even now, as elderly men, they have yet to receive messages of reconciliation from either the International Olympic Committee or the USOC.

They were never, of course, going to be feted as champions of free speech during Beijing. Perhaps this is a way London can have an edge. England, after all, takes pride in having led the path toward abolishing slavery.

In four years' time, when the Olympic spectacle turns Bulldog British for a fortnight, the geopolitical issues of the day will, of course, be everywhere about the Games. The Olympic stadium in London will be graced with the leaders of the free world. Imagine what it would say about the emancipation of the Olympic movement if Smith or Carlos were at hand to light the torch in London.

It may seem far-fetched, but was the theme of the biggest political rally since the heyday of Mao not all about embracing hope and change? If you had said to Smith or Carlos 40 - or even 20 - years ago their relationship with the Olympics could turn full circle, that they could come in from the cold and raise their hands anew, they would have laughed.

Of course, if you told them too that there would be a brother in the White House by that time, they would have said you were stone crazy.