The 1956 summer Olympics. The stadia were in place, the athletes were training on site; in just a fortnight, 68 nations would compete for the most prestigious medals in sport. Hang on. Make that 67. Pulling out from the Melbourne extravaganza at the eleventh hour: the People's Republic of China. Beijing withdrew its team because the International Olympic Committee (IOC) had allowed the Republic of China, aka Taiwan, to compete under its historical name of Formosa.

So when this year's hosts intone that politics should not intrude on the sporting progress of the Olympic flame, they indulge in some spectacular selective amnesia. And when those carrying the flame protest that they are honouring the Olympic ideal rather than endorsing or otherwise the Chinese track record on human rights, they demonstrate, at best, a colossal naivety.

The modern Olympics have always had politics as a bedfellow. There were other withdrawals in 1956, over Suez and the Soviet invasion of Hungary. China, again, was one of 62 countries that pulled out of the Moscow games in 1980, a year after the Russians had marched on Afghanistan - a tactic that prompted the Soviet bloc to shun Los Angeles four years later. Yet while these withdrawals signified massive disappointment for hundreds of athletes, it is possible to make a case for sporting boycotts representing a perfectly honourable means of engineering policy changes that have eluded political and diplomatic pressure.

The obvious example is apartheid South Africa, a nation whose pride in sporting prowess was woven deeply into the psyche of white participants and supporters alike. Cricket and rugby, the two sports that revelled in their all-white status, were the subjects of boycotts at various times. This was the nation that was going to refuse entry to an English cricket team because it contained a black star. So reviled internationally was this separatist sporting agenda that an astonishing 22 African nations pulled out of the 1976 Montreal Olympics in response to the IOC failing to exclude New Zealand following its rugby tour to South Africa.

Yet fast-forward to a time when boycotts and sporting isolation had played no little part in dismantling that apartheid mindset, and South Africa hosted the Rugby World Cup in 1995, reaching the final. The Springboks and their distinctive all-green jersey had once been one of the most hated symbols of white supremacy in black townships, so much so that those black sports fans who stood in their segregated pen in the national stadium did so to shout for whoever was playing the Boks. Now, as the finalists lined up, the new President of South Africa strode out to greet them in that self-same shirt, with the captain's number on his back. It was at once a political masterstroke and an act of consummate healing on behalf of Nelson Mandela. It was also the end of a skilful backstage campaign to woo white rugby and recruit it to the cause of inter-racial harmony; a strategy that also included the still overwhelmingly white team learning and subsequently belting out Nkosi Sikelele Afrika, the new anthem.

In short, sport is never just sport. It is used by good governments and bad as a symbol of a nation's virility. For countries such as Australia, it has the status of a national religion; for others, such as Kenya and Ethiopia, it offers a joyous celebration of athletic superiority. Watching soccer's Africa Cup of Nations earlier this year reminded you why the beautiful game earned that soubriquet before it fell into the hands of the overpaid and hopelessly spoiled brats of the developed world.

The quest for national sporting honour has had a chequered history. Sometimes the efforts to win at any cost have led to state-sponsored cheating alongside the more privatised variety. For all that, sport retains the ability to bring out the best and the noble in those blessed with talent and commitment. It still enthrals and enraptures those destined only to admire. The other week I was chairing an event where former Liberal Democrat leader Ming Campbell was promoting his autobiography - a book that is full of wonderful political gossip. The first four questions from the audience, however, were about his life as a Shettleston Harrier.

Sport matters. It matters to China's sense of itself and its reputation. Which is why it matters to Tibet as well. The stuttering progress of the Olympic flame's journey of "harmony" has been accompanied by much political posturing. But if it results in meaningful dialogue between Beijing and the Dalai Lama, the hijacking of its original purpose will prove justified.

For long years, Tibetan campaigners have waged a weary war in a deaf world. Sport, Olympic sport, has given them a voice that will not so easily be ignored or silenced.