Steven Mufson, energy correspondent for The Washington Post, is the author of “Fighting Years: Black Resistance and the Struggle for a New South Africa.”

In the mid-1980s, I spent two years covering South Africa and the black township uprising that would mark the beginning of the end of apartheid. Twice the government declared a state of emergency, jailing tens of thousands of people and sending troops to the townships in a futile effort to quell the rebellion against the country’s system of racial segregation.

Throughout that time, I never met or even saw Nelson Mandela; he was still languishing in Pollsmoor Prison. Jailed in 1962 and held mostly in the barren Robben Island prison, he would spend more than 27 years in custody.

Yet Mandela’s absence was very much a presence in everyday politics — the politics of waiting, waiting for the white ruling National Party to open negotiations with the only person who had enough stature to forge an agreement that would ensure a peaceful transfer of power and a democratic future.

Mandela, who at 94 now lies gravely ill in a Pretoria hospital, wasn’t just waiting. Every month, his captors allowed him to mail three letters to the outside world. The content of those letters, and Mandela’s choice of recipients, foreshadowed the political skills of reconciliation and inclusion that later marked his time as president and elder statesman. The letters showed that he was more than a symbol. Cut off from direct contact with people, Mandela deftly used them as a way of building alliances, reaching out to rivals and immersing himself directly in national politics. From his prison cells, he was preparing for the new South Africa.

“Dear Helen,” he wrote to Helen Suzman, a white woman who for years was the sole opposition member in the South African Parliament. “The consistency with which you defended the basic values of freedom and the rule of law over the last three decades has earned you the admiration of many South Africans.”

It was 1989, and Suzman had just decided to retire, a nonevent for many black South Africans who dismissed the apartheid-era Parliament — and even its liberal white opposition party — as pointless and unrepresentative. But Mandela, whom Suzman had visited in jail, managed to smooth over such differences without pretending they weren’t there.

“A wide gap still exists between the mass democratic movement and your party with regard to the method of attaining those values,” he wrote. “But your commitment to a non-racial democracy in a united South Africa has won you many friends in the extra-parliamentary movement.”

And he bid “fondest regards and best wishes to you and your family.”

Mandela reached across black political lines, too. One Christmas in the 1980s, the editors of a newspaper called the Sowetan were surprised to receive one of Mandela’s Christmas cards. The editors were sympathetic to the Pan Africanist Congress, the onetime rival of the African National Congress, which was founded in 1912 and was Mandela’s political home. But Mandela paid no heed to such divisions. “Best wishes,” the card read. “Keep up the good work.”

I learned about these letters in the course of my reporting; recipients usually described them with a sense of wonder. The letters were, of course, vetted by the security police officers who watched over Mandela. (One censor later sold a book based on what he had read in Mandela’s incoming and outgoing mail.) Yet I never heard of a letter that had been altered or of sections blotted out. It wasn’t necessary; Mandela was sensitive to those extra eyes.

He sent a polite note to his nephew Chief Kaiser Matanzima, the Transkei homeland leader. (Under apartheid, blacks were supposed to be citizens of these tribal homelands, mostly carved from the least desirable parts of the country.) At the time, homeland leaders such as Matanzima were being vilified by the ANC for collaborating with the government by accepting positions in the homeland structure. Avoiding politics, Mandela discussed family matters and said he looked forward to leaving jail and seeing him. The note softened the edges of their political differences.

Mandela even sent a note to Chief Mangosuthu Buthelezi, who was head of the KwaZulu homeland. In those days, the ANC was banned, but during the 1980s a coalition of community and political organizations, the United Democratic Front, had taken up the anti-apartheid banner. The UDF and Buthelezi were bitter rivals, and each claimed the mantle of the ANC. Buthelezi sought an audience with Mandela at Pollsmoor Prison, where Mandela had been transferred.

In his letter, Mandela declined Buthelezi’s request but in a manner that did not reflect poorly on the chief. He thanked Buthelezi for demanding the release of political prisoners, but said the timing for a visit was inopportune and urged him to meet with representatives of the ANC.

Eventually some of Mandela’s letters were published, along with excerpts from his diary, in a book titled “Conversations With Myself.” In one from July 1985, he tried to cheer up Archie Gumede, the UDF president, who was awaiting trial for treason. Gumede had also been charged with treason along with ANC leaders nearly 30 years earlier. In his letter, Mandela recounted how nine men had been condemned to death for treason by Queen Victoria, but after worldwide protests they were banished instead of executed. Eventually, Mandela reassured, one became prime minister of Australia, two became U.S. brigadier generals, and another became agriculture minister of Canada.

These letters didn’t always work magic. The letter to Buthelezi wasn’t enough to keep the chief from waging a bloody battle against his UDF and ANC-backed rivals. Only after Mandela’s release and considerable negotiations was he able to bring Buthelezi into the fold.

Still, the letters revealed Mandela as a master of the small gesture — a practice he continued as president, with real results. Among the Afrikaners most worried about a black-majority government, Mandela scored points by reaching out to the white captain of the Springboks rugby team and bringing the country together behind the overwhelmingly white squad. “He’s got such a common touch with people. He makes you feel at ease. He makes you feel important, and he takes time,” said Francois Pienaar, captain of the 1995 championship team. He recalled arriving in the changing room before the championship match and finding Mandela there “wearing a springbok on his heart. . . . I was so proud to be a South African.”

Mandela fully grasped the importance of political pluralism. As president, he did not arrest his critics, and he embraced reconciliation — fulfilling the promise of his prison-era correspondence.

I finally met him in Washington in the early 1990s. I had been expelled by the apartheid-era government and was covering economic policy for The Washington Post. Mandela was on a global tour, and he told me I was welcome to come back.

Mandela mixes humility, dignity, authority and determination. In an April 1985 letter to Sheena Duncan, a white woman who led the anti-apartheid group Black Sash, he wrote: “The ideals we cherish, our fondest dreams and fervent hopes may not be realised in our lifetime. But that is besides the point. The knowledge that in your day you did your duty, and lived up to the expectations of your fellow men is in itself a rewarding experience and magnificent achievement.”

Once he’s gone, there will be no more letters or graceful gestures. Many South Africans are nervous that racial tensions will rise in a post-Mandela South Africa.

“True leadership — the sort of visionary leadership that Mandela is famed for — leaves a legacy that outlasts its originator’s mortal flesh,” Verashni Pillay, the deputy editor of the Mail & Guardian Online, wrote this past week. “It bequeaths an idea that can live on without him or her, an idea that will take root and flower despite the intense and sometimes ugly obstacles thrown at it. And reconciliation, that painstakingly tough, monumental but necessary project, is one that belongs to all of us now.”

Today, politics in South Africa remains competitive and mostly peaceful, and reconciliation is a touchstone. Seeing that endure would be the best tribute to Nelson Mandela — the man, the symbol, the imprisoned correspondent.

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Steven Mufson covers the White House. Since joining The Post, he has covered economics, China, foreign policy and energy.