By David Smith

There were presidents and prime ministers, tens of thousands of people and an endless torrent of words. But one man was missing, both physically and figuratively: Nelson Mandela himself.

The former South African president’s body was not brought to the national memorial service in Johannesburg. His voice was not heard over the loudspeakers, though many others’ were. And in a peculiarly rambling, rain-soaked event that got bogged down in domestic politics and ended in a near empty stadium, it felt like Mandela’s soul was absent too.

Nearly a hundred heads of state had travelled from all corners of the world to remember Mandela, who died last week aged 95, at what had been billed as the biggest funeral ever seen. As he arrived, Sir John Major, the former British prime minister, said: “This is unique. I don’t think we’ve seen anything like this before and I don’t think we’ll see anything like it again.”

But it was a tribute that did not match the monumental stature of the man, nor ride the spontaneous wave of emotion witnessed on the streets in recent days. What should have been a poetic tribute to a giant of 20th century history was soon infected with the prose of local politics. Every time South African president Jacob Zuma‘s face appeared on the giant TV screens, sections of the crowd booed and whistled.

There was only one speaker who made everyone stop and listen. The cacophony of cheers and applause for Barack Obama – who on his way to the podium stopped for a historic handshake with Cuban president Raúl Castro – left no doubt of his continued political rock star status, at least in Africa.

Officials had predicted that the 95,000-seat FNB Stadium would be filled and some spectators turned away but, in the end, it only reached about two-thirds capacity. Constant rain drove people into the top tier, leaving thousands of empty seats exposed to the TV cameras. Some of the dozens of trains reserved to take people to the stadium were delayed because of a power failure. Umbrella-wielding spectators who sprinted to their seats from 6am – hours before proceedings got under way – danced and sang with gusto, creating an atmosphere more akin to a football match than a wake. “It’s more of a celebration that I expected,” David Cameron told the Guardian before taking his seat. “You can see the atmosphere in the stadium is really something else.”

The vast venue arguably called for a spectacle of Mandela’s life involving music, dance and archive footage on the scale of an Olympic opening ceremony. But instead it was a programme heavy laden with speeches by politicians that were not always audible over the sound system. As the crowd became restless, Nkosazana Dlamini-Zuma, the chair of the African Union, was drowned out by songs and vuvuzelas, the plastic horn widely used during the World Cup here in 2010.

For a long spell a section of the crowd turned their backs to the stage and instead stared upwards at a balcony containing Barack and Michelle Obama and former president Bill Clinton, wife Hillary and daughter Chelsea. VIPs and members of the public began filing out well before the end. When, after four hours, retired archbishop Desmond Tutu stood up to address a virtually empty stadium, it summed up the frustrated sense of what might have been.

At the heart of the event was a family in mourning. The sharpest emotion came when Mandela’s ex-wife Winnie Madikizela-Mandela kissed his widow Graca Machel, bent down and hugged her for several long seconds, then kissed her again. Both women, dressed in black, had been at Mandela’s bedside at the end. Four of Mandela’s grandchildren made speeches.

Friends and old rivals gathered too. George Bizos, Mandela’s lawyer for half a century, had witnessed him address 80,000 people at the same stadium shortly after his release from prison in 1990. “It’s raining and one sage said it’s because the clouds are crying,” said Bizos, tears welling in his own eyes. “We are saddened by his passing but we have to be stoical about it. None of us is immortal. He had a good innings.”

FW de Klerk, South Africa‘s last white president, who 20 years ago to the day had shared the Nobel peace prize with Mandela, said: “I’m very sad but very thankful that the nation is coming together in this wonderful way. I think that’s how he would have wanted it.”

Tutu greeted Bono with kisses on the cheeks, while other guests included actor Charlize Theron and model Naomi Campbell. The national anthem was sung, prayers of different faiths were held and, with a few musical interludes, the long series of speeches got under way. In a sign of shifting global winds, four of the five Brics countries were represented – Brazil, India, China and South Africa – while Europe, including former colonial powers Britain and the Netherlands, were sidelined.

But Obama was on vintage form. “Nelson Mandela reminds us that it always seems impossible until it is done,” Obama told the gathering. “South Africa shows us that is true. South Africa shows us we can change. We can choose to live in a world defined not by our differences but by our common hopes. We can choose a world defined not by conflict, but by peace and justice and opportunity.”

At one point, Obama quoted the closing sentences of Mandela’s celebrated speech from the dock at the Rivonia trial in 1963. From one great orator to another, the words of South Africa’s first black president were now in the mouth of his American counterpart, electrifying the crowd.

Obama went on make what could be seen as remarks aimed at some of the African and world statesmen present. “There are too many of us who happily embrace Madiba’s legacy of racial reconciliation, but passionately resist even modest reforms that would challenge chronic poverty and growing inequality. There are too many leaders who claim solidarity with Madiba’s struggle for freedom, but do not tolerate dissent from their own people. And there are too many of us who stand on the sidelines, comfortable in complacency or cynicism when our voices must be heard.”

The US president added: “While I will always fall short of Madiba’s example, he makes me want to be better. He speaks to what is best inside us. After this great liberator is laid to rest; when we have returned to our cities and villages, and rejoined our daily routines, let us search then for his strength – for his largeness of spirit – somewhere inside ourselves.”

South African users on Twitter immediately united in praise for Obama for rising to the occasion. “No better speech can be given for Tata Madiba than that one right there!” posted one. “Thank you President Obama for such amazing words #MandelaMemorial.”

Some contrasted his eloquence with Zuma, who looked glum each time his face was shown and roundly booed. It was a thankless day for the South African president who already found himself in Mandela’s shadow. Even his predecessor Thabo Mbeki and Zimbabwean president Robert Mugabe got warmer receptions when the cameras turned on them.

The public hostility during what was supposed to be a memorial service laid bare the current level of anger towards Zuma, who has been embroiled in a series of scandals including the spending of taxpayer millions on a swimming pooland other improvements to his home. With a national election due in the next six months, the cracks in the post-Mandela African National Congress are beginning to show.

Justice Malala, a political analyst, said: “The politics of South Africa today marred it even further when Zuma was booed. We’ve been sitting in such a bad place that we had domestic politics spilling over into a celebration of Nelson Mandela’s life. Tomorrow we’ll all be talking about Zuma’s political fortunes.”

Reflecting on the anti-climactic service, Malala said: “It failed to live up to the spirit of Nelson Mandela. It was an absolutely joyless experience. It was so un-Nelson Mandela. When the big moment came, South Africa didn’t live up. They didn’t play. It was for the elite and there was nothing of the spirit of Nelson Mandela here. It was the most joyless celebration compared to what we’ve seen outside his old homes in Soweto and Houghton.”

Mandela will lie in state in Pretoria from Wednesday to Friday. South Africa has one more chance to get it right when he is buried in his ancestral village of Qunu on Sunday.