It is more than a decade since Clare Short wrote the extraordinary letter that some have characterised as 'the spark' that set off Robert Mugabe. Zimbabwe's President was pressing Britain to fulfil a commitment to pay for land redistribution from white farmers to poor black people, which he regarded as a pillar of the deal that brought an end to Ian Smith's unilateral declaration of Rhodesian independence and the birth of a free nation in 1980.

Taking back the land was a key platform of the liberation war and, Mugabe said, the time had come for London to honour its commitment. Short, in the letter to Zimbabwe's Agriculture and Land Minister, Kumbirai Kangai, in late 1997, repudiated the claim. 'I should make it clear that we do not accept that Britain has a special responsibility to meet the costs of land purchase in Zimbabwe. We are a new government from diverse backgrounds without links to former colonial interests. My own origins are Irish and, as you know, we were colonised, not colonisers,' she wrote.

Short, then International Development Secretary, said that Britain would help pay for long-term redistribution only as part of an agreed poverty alleviation programme, but added that it would be 'impossible' to support rapid land acquisition because of the damage it would cause to agriculture.

Given how things have turned out, that might seem a reasonable position. But Short was in essence saying that the past was done with, because Britain was no longer an imperial power and that Zimbabwe's liberation war was history. Her letter laid bare a fundamental misunderstanding of Mugabe and the nature of the regime he leads, a mistake that others - including Zimbabwe's whites and a rising black opposition - were to repeat as they struggled to prise him from office and that has, arguably, helped him cling to power.

Britain did have a special responsibility, not only as the former coloniser but also because it had failed to act against Smith's illegal regime - making necessary a liberation war that cost tens of thousands of lives, most of them black - on the grounds that it could not move against its 'kith and kin' in Rhodesia, in Harold Wilson's phrase. It was those kith and kin who made the same mistake as Short in thinking the past was history.

When the farm invasions began eight years ago, it would have taken a particularly hard heart not to be moved by the sight of people forced from their homes at machete point, sometimes losing everything but their lives, desperately fearful for the safety of their children.

But looking around those farms as the white families fled, it was also apparent that independence had not done much for the daily lives of their workers. Often they still lived in rows of cramped, bare accommodation, sometimes all too reminiscent of prison cells, built in colonial days. Liberation had not changed the fundamental link between being white and rich and being black and poor.

Zimbabwe's whites were not only complacent; they also misjudged how Mugabe saw their place and the unwritten pact that allowed them to stay on. In the cities they kept their houses and their pools and their servants. Life went on as before, but without the war.

The white farmers had it even better. With crop prices soaring, they bought boats on Lake Kariba and built airstrips on their farms for newly acquired planes. Not much of that trickled down to the poor, and not many of the farmers reflected on the essence of the liberation war and its cry not only for freedom but also for land. Instead Zimbabwe's whites reached an implicit compact with Zanu-PF; they could go on as before, so long as they kept out of politics and did not criticise publicly.

That is the way it stayed for 20 years, but then quite a number of whites - some of them farmers - made a misjudgment. They thought they had the same rights as everyone else.

It began with the visible and extensive white opposition to Mugabe in a constitutional referendum in 2000, which he was shocked to lose. Mugabe went on television to concede defeat. Emboldened whites stuck their heads above the political parapet, imagined that the old man could be driven from power and threw their support behind the fledgling Movement for Democratic Change under Morgan Tsvangirai at the parliamentary elections a few months later.

White people accounted for only a small proportion of the party, but they were highly visible and had clout in part because they were the ones with the money and the cars. They could be seen delivering party propaganda and running its offices. White farmers appeared on stage with Tsvangirai, handing over fat cheques to party coffers.

The MDC and its white activists regarded all that as everyday politics in a normal society; Mugabe and the Zanu-PF old guard saw an attempt to refight the liberation war by other means. Their fears were not entirely unfounded.

A man called 'Monty' Montgomery was heading the MDC's campaign in the Hurungwe and Kariba regions in the 2000 election. His family lineage in Zimbabwe went back to the 1890s. His parents were teachers in Bulawayo, at a school once attended by Hendrik Verwoerd, the architect of South Africa's apartheid. Montgomery was conscripted into the Rhodesian police and rose to become an officer in the notorious special branch responsible for the interrogation of political prisoners and 'terrorists' - men like Mugabe.

By the time I met him, Montgomery was running an agricultural supply business that had fallen on hard times. He had not taken much interest in democracy until his pocket was hit, but talking to him, and to other older whites, there was a sense that this was payback time, an opportunity to 'get' Mugabe.

When 5,000 black MDC delegates elected the party's executive in January 2000, three out of the top four were whites. The head of the party's campaign in Mashonaland West, Duke du Coudray, explained it this way: 'There's only one reason we whites are so visible. The mass of this party is black, but the black bourgeoisie is afraid to take a public stand. They are intimidated away from public support. They are pushing us to the fore, saying we support you, but we can't do it in public.' What the whites did not understand was that they could not do it either. They might have had a legal right, but the history was too recent and they soon found themselves exploited by Mugabe as targets and scapegoats. Far from bringing him down, they had helped to strengthen him.

Tsvangirai welcomed whites for sound reasons, but it proved to be a misjudgment to allow them such a public role while maintaining an equivocal policy on land redistribution that fed Mugabe's claim that the MDC would give the farms back to their former owners.

The opposition leader made other political misjudgments that Mugabe exploited. Tsvangirai was paralysed by indecision after Zanu-PF stole the 2002 election and failed to mobilise the mass of MDC supporters in the crucial days following the vote, when many were ready to take to the streets. The opposition had again failed to appreciate the measure of Mugabe, imagining that, if he lost the election, he would simply step aside - and so it had no Plan B.

Tsvangirai also failed to appreciate how well Mugabe would exploit his liberation credentials in the rest of southern Africa. He portrayed the MDC as a neo-colonial conspiracy in which blacks were a front for unreconstructed Rhodesians. When the farm seizures began, the region's leaders threw their weight behind Mugabe, accusing his detractors of ignoring history. Joachim Chissano, then President of Mozambique, defended Mugabe by saying that there was a tendency to 'put a blanket' over the history of the independence struggles in Africa. He condemned those who would portray 'former heroes of the freedom struggle' as 'anti-democratic and even dictators'.

A couple of years later, as Mugabe bludgeoned and murdered his way to a rigged election victory, Chissano said: 'There's nothing the world has to teach Robert Mugabe about the rule of law.'

Britain didn't help by wading in with loud denunciations. Peter Hain, then Africa minister, called Mugabe's government 'uncivilised'. Hain might have given more thought to how other African leaders would view a minister of a former colonial power, who was also the product of an apartheid-era whites-only school in Pretoria, describing one of their number that way.

Thabo Mbeki had not long before become South Africa's President. He views politics and much else besides through a racial prism in a way that Nelson Mandela does not. Rainbow nation man had given way to Zebra man. The highly visible white involvement in the MDC made Mbeki twitchy. The region's leaders decided to put him in charge of dealing with the Zimbabwe problem and Mbeki embarked on his 'quiet diplomacy' that had one aim - to ease Mugabe from power with dignity, but keep Zanu-PF in control. Quiet diplomacy did not mean remaining silent in public; it meant refraining from criticism. Mbeki frequently justified actions by Mugabe.

So it was that, last Sunday, at a dinner at the South African High Commission in London, he endorsed the recent election whose result we are still awaiting. 'We have been very pleased with the manner in which the elections were conducted: the opposition had access to every part of the country, there was no violence, no one was beaten up; it's gone very well. You have a very serious effort by the people of Zimbabwe to resolve their problems, we could see there was a common spirit among them and that's the sense we got. And in the conduct of the election none of the parties came back to us to intervene to say something was going wrong,' he said.

Mbeki's yardstick for a fair election was that no one was murdered or beaten, as occurred in the previous three presidential and parliamentary ballots. But by almost every other measure, it was far from free. Most of the opposition media, including the main daily newspaper, have been banned for years, while the state-run press ran a vitriolic hate campaign against the opposition. Parliamentary constituencies were gerrymandered to diminish the power of opposition voters. The electoral roll contained hundreds of thousands of ghost voters.

By the time Mbeki gave his speech, the opposition was saying something was very wrong.

South Africa's Deputy Foreign Minister, Aziz Pahad, publicly bought the line that the result of the presidential election was not being released for logistical reasons, and said that sceptical reporters were 'instruments of conspiracy and destabilisation'. Mbeki said much the same in accepting that the election commission was 'verifying' the results. The practical effect was to give Mugabe time to unleash his forces to terrorise Zimbabweans to ensure they do not again vote against him in the second round of elections that the election commission was trying to engineer. Mbeki flew into Harare yesterday to meet Mugabe and emerged from their talks again saying there is 'no crisis' and once again appealing for patience until the results are released. Mbeki's principal contribution over recent days has been to try to arrange what he always wanted - Mugabe out, but Zanu-PF still in power. He is also insisting that, if Mugabe goes, it must be without humiliation. To Mbeki, the pipe-smoking, urbane intellectual, the dignity of an African leader is more important than the indignity of Africans scrabbling on rubbish dumps for food, dying in hospitals for want of drugs, or forced to crawl through barbed wire into a foreign country to find work.

The region's leaders have spent years indulging Mugabe. Now he is snubbing them by refusing to attend their summit in Zambia to discuss his country's crisis.The coming days will show whether Mugabe's useful idiots will finally do right by the people of Zimbabwe.