The fall of the Berlin Wall and the release of Nelson Mandela are two of the most joyous and momentous events of the past half century. The collapse of communism changed Europe for ever. The dismantling of apartheid spared South Africa a bloodbath and set the world an extraordinary example of reconciliation and racial harmony. Who could have imagined the two events were so closely linked?

Twenty years after the Wall was breached and almost two decades since Mr Mandela was freed, the architects of these astonishing events met in Berlin this week to celebrate what they unleashed and their consequent Nobel Peace Prizes.

Mikhail Gorbachev is older and plumper than he was when, as Soviet President, he warned the ageing and intransigent East German leader Erich Honecker that “history punishes those who come too late”.

F. W. de Klerk seems more mellow than he was when, as President of a pariah state, he ordered the guards to unlock the cell holding the world’s most famous political prisoner. But both still exude that aura of men who have changed history. Both can command attention by the very fact of the immense power that they once exercised, and which they used not to do evil but to do good.

Although from opposite ends of the political spectrum and from countries that saw each other as the incarnation of evil, in uncanny ways they resemble each other. They look somewhat alike. Both are creatures of the blinkered systems that nurtured them: Mr Gorbachev was a leader of the communist youth league who grew up under Stalin and held his first party post in 1955; Mr de Klerk, the son of a South African senator, was first appointed a minister 31 years ago, when the National Party was vigorously implementing new measures to strengthen apartheid.

Each came to power at an early age, supported by an embattled Establishment that saw them as tough and vigorous modernisers. Each was acclaimed as a leader who would defend the system, communism or apartheid, against enemies abroad and weaknesses at home. And each soon realised, as he looked at the economic statistics, the political options and the internal contradictions, that the system he had inherited was rotten to the core.

It takes courage to admit, in middle age, that an ideology with which one is imbued and a political system of which one is part have failed. It takes even more courage to persuade others of this. Both Mr Gorbachev and Mr de Klerk knew they had to make changes. Neither knew where these would lead.

Mr Gorbachev was never a visionary or a revolutionary. He was a pragmatist, although a somewhat naive one. He thought that communism could be reformed through his two guiding principles of glasnost (openness) and perestroika (reconstruction). He hoped communism would evolve into a kind of Swedish social democracy. He found, instead, that every change necessitated ever more radical change if the State was to remain viable. He hoped that in Eastern Europe he could replace the corrupt dinosaurs with younger, liberal communist leaders who would answer the longing for the liberties and consumer goods of the West.

He lost control of his changes, however. Abroad they ended in uprisings across the Eastern bloc and the destruction of a hated Wall that fell, appropriately, almost exactly 200 years after the fall of the Bastille. At home his experiments ended in his political fall.

Mr de Klerk, also no radical, was more able to keep control, because fellow Afrikaners, even at the heart of the Establishment, realised that the economic reasons for segregation no longer made sense. For about 80 years the percentage of black South Africans holding skilled middle-class jobs had remained the same. But in the 1970s and 1980s it rose swiftly. Millions of blacks and whites were doing the same jobs but being paid and treated differently.

Sitting on the same podium in Berlin as Mr Gorbachev, now a firm friend, Mr de Klerk declared that it was only the fall of the Wall that emboldened his party to take the risk of releasing Mr Mandela. For years, South Africans had feared that communist infiltration of the African National Congress would mean an inevitable victory for communism if it were legalised and came to power. “The ANC would come in on a platform of racial equality. We thought it would then be overtaken by a communist coup,” he said.

Only when it was clear that communism was no longer a world force did the National Party speed up negotiations with the prisoners on Robben Island that led, in 1990, three months after the fall of the Wall, to Mr Mandela’s release.

The symbiosis goes farther. Mr de Klerk and Mr Gorbachev are eager to put themselves retrospectively on the right side of history. Mr Gorbachev said this week that when he visited East Berlin earlier in 1989 he saw the yearnings of Germans to be free and united. He did not show it at the time.

Mr de Klerk has now become a fervent champion of the man with whom he had a prickly relationship in the first post-apartheid Government. “It is only thanks to Nelson’s Mandela’s leadership, his tolerance, his remarkable lack of bitterness that South Africa is today peaceful and prosperous,” he declared in a spontaneous salute to United Nations resolutions proposing a Nelson Mandela day. That is not an assessment he would have ventured in 1990.

A Nobel Peace Prize confers a moral and humanitarian reputation on its recipients that tends to spur them either to greater efforts or to new and more ambitious causes. It has certainly made Mr Gorbachev and Mr de Klerk the radicals they never were in their youth. The former Soviet President is now a fervent environmentalist and founder of the Geneva-based Green Cross, who campaigns against nuclear weapons, nuclear power and for clean air, water and industry.

Mr de Klerk, the only President to have scrapped a country’s nuclear weapons, campaigns tirelessly against nuclear weapons, for African development and against Aids. Both intend still to change history again.

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