Nearly half a century before this weekend's trip to South Africa by President Barack Obama, a visit by Robert F. Kennedy at the height of apartheid oppression was described by a newspaper editor as "the best thing that has happened to South Africa for years."
"It is as if," wrote the editor of the Rand Daily Mail in 1966, "a window has been flung open and a gust of fresh air has been swept into a room in which the atmosphere had become stale and foetid."
Robert and Ethel Kennedy's car was mobbed in Soweto. More than 30,000 people heard him speak in four cities. He took a helicopter to visit the banished 1960 Nobel Peace laureate and African National Congress leader, Albert Luthuli, and pronounced him "one of the most impressive men I have met." He met students and business leaders in the Afrikaner university town of Stellenbosch. There was no reported contact with the apartheid government.
Americans remember the keynote speech of the trip for Kennedy's imagery evoking the "ripple of hope" sent out – in the language of the time – "each time a man stands up for an ideal, or acts to improve the lot of others, or strikes out against injustice..."
But for many South Africans, the most memorable words were those with which he opened:
"I come here this evening because of my deep interest and affection for a land settled by the Dutch in the mid-seventeenth century, then taken over by the British, and at last independent; a land in which the native inhabitants were at first subdued, but relations with whom remain a problem to this day; a land which defined itself on a hostile frontier; a land which has tamed rich natural resources through the energetic application of modern technology; a land which was once the importer of slaves, and now must struggle to wipe out the last traces of that former bondage. I refer, of course, to the United States of America."
Kennedy's identification of the United States as labouring under a history which mirrored that of South Africa, and his acknowledgement of both nations' shared failings, resonated strongly with South Africans.
It's hard to imagine how the South Africa which Barack Obama will experience this weekend could be more different. But the challenge he faces in striking the right notes with Africans, both in South Africa and beyond, is as daunting.
For President Obama has arrived in a country which is becoming convulsed in a process, as yet inchoate and not fully comprehended by South Africans themselves, of coming to terms with the passing – whenever it may happen – of their George Washington.
The events that are playing out on the streets around the hospital where Graca Machel quietly sits holding the hand of Nelson Mandela, who is reportedly on life support, are not unlike those seen in London after the death of Princess Diana, or on the streets of lower Manhattan in the weeks and months after the 2001 attacks on the World Trade Center.
South Africans of all backgrounds and stations in life are gathering in increasing numbers around the hospital. Their reasons for going are as varied and, often, as confused as those of the Americans who waited in long lines to stare at the rubble of the Twin Towers after 9/11.
Many want to leave flowers, light candles or pin up hand-written messages and posters. Others come to look at them. A choir releases balloons and sings. Attention-seekers of different stripes seek out the TV cameras. Politicians exploit the spectacle. Children pray for Madiba's recovery. An archbishop goes inside to pray with the family for a "perfect, peaceful" end.
Above all, one suspects, many ordinary citizens want simply to feel close to their beloved Madiba.
The first hurdle the Obama entourage faces in coming to terms with the national mood will be in their actions. They will need to show more sensitivity to the national sovereignty of their host country than is often customary for visiting Western leaders.
Africans are usually too polite to say it, but as hosts they resent being instructed by British diplomats, for example, on how long a church service – and the sermon – should be when the Queen of England visits, as once happened in Cape Town. Or to then First Lady Hilary Clinton's staff re-arranging furniture, without any consultation with their hosts, two minutes ahead of a photo op – as happened at the Truth and Reconciliation Commission in 1997. Overhearing beneficiaries of U.S. aid grants this week, there were suggestions of similar pressures.
But President Obama's biggest challenge will be to find the words which resonate with a nation on the verge of grief. He has a limited number of opportunities to do so. Saturday's news conference with President Jacob Zuma is a possible, although it would seem, an unlikely one. Perhaps speaking to students at the Soweto campus of the University or Johannesburg, or a state banquet later in the day.
Or, if he's ambitious, his best chance will come on Sunday evening. The White House has announced that the speech advertised for his last night in South Africa will be the "main framing speech of the trip about our Africa policy".
As the venue, they have chosen the University of Cape Town – noting that it is the "historic" site at which Robert Kennedy spoke in 1966.
John Allen, the executive editor of allAfrica.com, has also worked for Desmond Tutu, South Africa's Truth and Reconciliation Commission, and the Parish of Trinity Church, Wall Street, during and after the 9/11 attacks.