It is something Bob Geldof always said he would not do: Live Aid II. Over the past 20 years, the campaigner for Africa has been inundated with requests by worthy causes wanting his endorsement of whatever grand scheme they hoped to embark on. Many of them involved requests for another concert on an epic scale.
He has never even been tempted. "It's a failure of imagination, they need to think of something new," he would say, whenever anyone proposed trying merely to replicate the 1985 global concert. "And anyway Son of Live Aid can never have the impact of the original."
To understand why, it is essential to think back to the world in which the concert took place on 13 July 1985 - that day when the entire globe seemed to come together with a single common purpose and raised over $100m, the most by far that had ever been collected for charity by a single event.
The concert was a response to a famine in which some 30 million people were suffering as drought swept across sub-Saharan Africa. Such terrible events had happened before. What was different about this one was the immediacy with which it reached the television screens of the affluent world. Children were dying before our very eyes, as we sat in our comfortable living rooms.
On the day of the Live Aid concert the world stopped what it was doing to unite in a clear moment of absolute certainty. The largest audience ever seen - more than a billion and a half people, across the planet - joined together to do something unequivocally good.
Something changed inside those who watched the television that day - including the young Tony Blair and Gordon Brown, who have since gone on to make a massive step change in British policy towards Africa. Such was the emotional power that, as the man who is now Chancellor of the Exchequer recently recalled, a poll a few months back named Live Aid as the single most important public event in the lives of two generations.
"We can never recapture that," Geldof would moan softly as his aides repeatedly insisted that the time had come for another major international mass action. But there was something else. It is hard now to comprehend what a technological feat the original concert had been. In 1985 there were no mobile phones and barely any fax machines. The laboriously punched ticker tape of the telex was the standard form of written international communication. In many countries international phone calls still had to be booked, sometimes hours in advance, through the operator. Computers were outside the experience of most ordinary people. The e-mail was a future dream. It seemed a challenge bordering on the impossible to broadcast the first absolutely live, all-day, multi-artist concert to the whole world.
Yet simultaneous concerts on two continents were co-ordinated. Global television schedules were cleared. Concorde was put on standby. Even the Space Shuttle astronauts were lined up to make a contribution. That day 98 per cent of all the television screens in the world received the broadcast and viewers felt part of the biggest collective event in human history.
"How can we match that achievement in an era in which satellite broadcasting makes global communication a routine, easy, everyday experience," asked Geldof. "In 1985 to see all the biggest bands in the world in one go was a unique event. Today you can see them all any day on MTV."
Until only a matter of weeks ago, Geldof was repeating this same line in private with his fellow campaigners. So what changed his mind?
The shift began in the seven months that he and I worked for Tony Blair's Commission for Africa. The experience surprised Geldof. The impetus for launching the commission had been Bob's. His initial impression on a visit to Ethiopia at the start of 2004 was that nothing had improved in the 20 years since Live Aid. All that effort had been for nothing, he railed, when he contacted Tony Blair from Addis Ababa. "Africa," he told Blair in characteristically Geldofian language, "is fucked".
But what he discovered in extensive travels round the continent over the months that followed was the exact opposite. Things are starting to improve in Africa. After nearly 40 years of stagnation, a good number of African countries are seeing the beginnings of real economic growth. Fledgling democracies now outnumber dictatorships by a significant number. Of course, the continent still needs greater peace, better government and a crackdown on corruption. But many African governments are now beginning to address these issues. But the commission's report concluded that without the backing of the rich world these green shoots of recovery would be burnt up by the merciless African sun. The industrialised nations needed to do three things. First, they must announce an immediate plan to wipe away 100 per cent of the debts of the world's poorest countries. Second, they must double levels of aid to $50m. And third, they must reform world trade to end its bias against the poor.
In the weeks that followed the report's publication, Geldof's fears steadily grew that the rich nations would not deliver on the big push across a broad front which is what makes the commission's recommendations different from all previous piecemeal initiatives on Africa. The US and Canada refused to sign up to the International Finance Facility which Gordon Brown had devised to finance the package. And Washington refused to agree to his plan to sell off some of the IMF's gold reserves to finance debt cancellation.
When Geldof's fellow rock star campaigner Bono told the US Secretary of State Condoleezza Rice at a private meeting that during U2's US tour he would get 10,000 fans a night to call the White House, she simply replied: "We can take the calls." The picture is not totally gloomy. Far from it. The French, British, German, Canadian and Japanese governments have all indicated that they are prepared dramatically to increase their aid budgets, some of them using mechanisms other than the IFF. European Union ministers have agreed a virtual doubling of the EU's combined aid by 2010, passing the 0.51 per cent mark on the way to the UN target that rich nations should spend 0.7 per cent of their national income on aid - and putting greatly increased pressure on the United States and Japan to do the same. And the signs in Washington are that the Bush administration has begun behind-the-scenes negotiations with Congressional appropriation committees to find the money to announce a last-minute deal before the G8 summit at Gleneagles in July.
Still Geldof was determined to maintain the pressure to see that the result at Gleneagles did not offer only gestures or half-measures. "This is the best chance for Africa for a generation," he kept saying. "We can't afford to blow it."
Throughout all this his mind was turning on the idea of another Live Aid concert. The first had been the greatest charitable event the world had ever seen. But now something different was needed: not Live Aid II but Live Eight - another international mass action on an epic scale, but this time aimed at securing justice for Africa from the G8.
"What about this," he said, suddenly afire with excitement, "simultaneous concerts in London, Paris, Berlin, Rome and New York, at the end of which we ask everyone to get up and begin the Long Walk. Not the Long Walk to Freedom of Nelson Mandela's autobiography but a Long Walk to Justice, a march to get a million people in Gleneagles."
Calls were made to Live Aid veterans including U2, the Rolling Stones, Paul McCartney, Pete Townshend, Mark Knopfler and Elton John, and to a new generation from the pop music firmament including Coldplay, Oasis, Robbie Williams, the Stereophonics, The Darkness, Keane and Travis.
He rang Harvey Goldsmith, the impresario who did the original Live Aid. He travelled to Rome to get the Pope's backing. He placed calls to various Hollywood stars to see if they would put their private jets at the disposal of campaigners wanting to fly across the Atlantic. He dreamt up the idea of a Dunkirk-like flotilla of little boats to ferry activists from Europe across the channel. He asked Richard Branson for a free transatlantic plane and a train or two. He contacted ferry companies to ask for transport across the Channel for activists from Paris, Berlin and Rome. And bus and coach companies to set up transport within the United Kingdom.
As the logistics were explored, various authorities put up objections to the use of certain parks, premises and facilities. To gain maximum impact, Live Eight should be on 2 July, the Saturday before the G8; that was not long enough to actually walk to Gleneagles. How could a million people be got there? Where would they sleep once they arrived?
As the difficulties were resolved and new ones arose, Bob Geldof's mood would oscillate wildly. Time after time he threatened to call the whole thing off. All the problems are still far from solved. But the same manic conviction which had driven the original Live Aid had returned. The Road to Gleneagles will not be easy but the Long Walk to Justice has begun.
1985 vs 2005: The battle of the bands
Sting Live Aid kick-started Sting's extraordinary solo career. His set finished with two Phil Collins duets - the only way from there was up.
Status Quo The Quo started with "Rockin' all Over the World" and finished with something that sounded a lot like it.
Style Council Ten years before his success with Stanley Road, band-hopping frontman Paul Weller was the face of this mod-rock outfit. He soon left to plunder solo riches.
Nik Kershaw Sporting a criminally offensive mullet, Kershaw managed to waste 18 minutes of valuable stage time with his unique brand of synth-rock nonsense.
Run DMC Before the world knew them as Aerosmith's collaborators on "Walk this Way" Run DMC were one of hip hop's pioneers. The only urban act on the Live Aid playlist.
U2 Bono, the Edge, Adam and Larry had just released The Unforgettable Fire. The moment when Bono invited a young fan onstage is marked in history as the moment he transformed from badly shorn boy into a bona fide rock god.
Sting Twenty years on, Sting has become one of the world's richest solo artists, embraced tantra, and forgotten those Phil Collins duets.
Franz Ferdinand Having spearheaded the new-wave revival, Eighties throwbacks Franz Ferdinand should have no problems performing at another old skool institution.
The Spice Girls - If rumours are to be believed, this perky Girl-power-peddling fivesome will be back together for one night only.
Robbie Williams He used to be the fat dancer from Take That. Now he's a global star with an ego the size of Stoke and commitment issues. The Live Aid audience might just be big enough for him.
Oasis Beatles, Stones and Stone Roses clones they might be, but Oasis are one of the most impressive stadium acts in living history. Live 8 would not be the same without them.
U2 They went global in 1985. They return to the Live 8 stage as the Biggest Rock Band in the World, with a soon-to-be beatified Bono up front.