Enough is enough. The publicity for the death and funeral of Nelson Mandela has become absurd. Mandela was an African political leader with qualities that were apt at a crucial juncture in his nation's affairs. That was all and that was enough. Yet his reputation has fallen among thieves and cynics. Hijacked by politicians and celebrities from Barack Obama to Naomi Campbell and Sepp Blatter, he has had to be deified so as to dust others with his glory. In the process he has become dehumanised. We hear much of the banality of evil. Sometimes we should note the banality of goodness.

Part of this is due to the media's crude mechanics. Millions of dollars have been lavished on preparing for Mandela's death. Staff have been deployed, hotels booked, huts rented in Transkei villages. Hospitals could have been built for what must have been spent. All media have gone mad. Last week I caught a BBC presenter, groaning with tedium, asking a guest to compare Mandela with Jesus. The corporation has reportedly received more than a thousand complaints about excessive coverage. Is it now preparing for a resurrection?

More serious is the obligation that the cult of the media-event should owe to history. There is no argument that in the 1980s Mandela was "a necessary icon" not just for South Africans but for the world in general. In what was wrongly presented as the last great act of imperial retreat, white men were caricatured as bad and black men good. The arrival of a gentlemanly black leader, even a former terrorist, well cast for beatification was a godsend.

Visiting and writing about South Africa in the last years of white rule in the 1980s, I was acutely aware that the great struggle was not so much between the white South Africans and Mandela's ANC, whose leaders were in prison or exile, but within Afrikanerdom. This was no rebellion against a foreign power. It was a potential conflict between an impotent majority and a potent minority, in which the likelihood of the latter giving way to the former seemed minimal – and unnecessary in the short term.

The first hero of that struggle was the then prime minister, FW de Klerk. The realisation that his group should cede power to a black government was a moral conversion as much as realpolitik. The Afrikaners capitulated not because some mighty power (such as sanctions) had crushed them or because of the more significant fall of Rhodesia and the Portuguese empire. Their priests and intellectuals told them apartheid had lost the argument. They had lost the will. It had been, said De Klerk, "a terrible wrong".

Even so the task of switching to black majority rule was Herculean, and success by no means inevitable. A lesser man than De Klerk could well have battled on for another decade of mounting bloodshed. But his tribal revolution, well chronicled by the historian of Afrikanerdom Hermann Giliomee, succeeded. It was a rare case of an entrenched minority peacefully handing power to a majority.

Mandela was crucial to De Klerk's task. He was an African aristocrat, articulate of his people's aspirations, a reconciler and forgiver of past evils. Mandela seemed to embody the crossing of the racial divide, thus enabling De Klerk's near impossible task. White South Africans would swear he was the only black leader who made them feel safe – with nervous glances at Desmond Tutu and others.

South Africa in the early 90s was no postcolonial retreat. It was a bargain between one set of tribes and another. For all the cruelties of the armed struggle, it was astonishingly sparing of blood. This was no Pakistan, no Sri Lanka, no Congo. The rise of majority rule in South Africa was one of the noblest moments in African history. The resulting Nobel peace prize was rightly shared between Mandela and De Klerk, a sharing that has been ignored by almost all the past week's obituaries. There were two good men in Cape Town in 1990.

The concept of goodness in a political leader has fascinated scholars from Plato to Nietzsche and beyond. We need to believe in it, lest we slide into cynicism, yet must beware of it lest we slide into idolatry. Machiavelli would have argued that it was easy for Mandela to be good. He was in prison and his courage was essentially personal. His moment of true goodness was brief. He understood from his study of British law the concept of legitimacy in government and the role of compromise. To them he added an instinct for reconciliation, but in part because he knew that without it he was unlikely to win.

Once that instinct had unlocked the door of a settlement, Mandela acted swiftly to reassure white businessmen who could well have vanished overseas. He welded the ANC into an electoral force, and worked to keep dissident Zulus on board when Natal secession briefly threatened. But as David Beresford's admirable Guardian obituary relates, he was a worse than ordinary president. He did little to resist the drift to cronyism and corruption, was a poor executive, and never deployed his talents to tame Mugabe or ease the horrors afflicting the rest of Africa. He preferred to see out his office meeting celebrities and raising dubious money.

Human history may crave myths, but needs to know them as such. I once argued with the writer Jan Morris against the nonsense attributed by some Welsh to Owen Glendower. She protested that "truth" in history was what people came to believe it to be. All tribes need legends, the better to cement their identity. Legends are not made to be true.

Yet history is a discipline not a faith. The world may crave a "Mandela-like icon", but to what end? For serious media outlets to discuss him alongside Mother Teresa, Gandhi and Jesus of Nazareth is barking mad. He was Nelson Mandela. After seeing their former president doused in virtue and squeezed dry of glory by an assembly of world celebrities, South Africans should repatriate his reputation. Mandela gave them signal service for a brief few years in the 1990s, and if it suits them to revere him as a symbol of unity, goodness and peace, so be it. That is their business.

But the South African quality I recall Mandela possessing to the full was not saintliness, it was a hardened sense of irony. I doubt if he is wearing the BBC's tin halo right now. I would bet he is laughing his head off.