He has been saying that for 10 years now. It is half true. Ever since the concert in 1985, which brought one-and-a-half billion people together through satellite link-ups in the world's largest concert and raised a total of $100m for the relief of the famine that was scourging sub-Sahelian Africa, Bob Geldof has been associated in the minds of the public with the alleviation of poverty among the world's poorest citizens. Routinely, ever since, he has been deluged by requests from worthy organisations asking if he could help them with just one more thing. Routinely he has said no. "I'm utterly brassed off with it," he once told me, "I've given up almost two years of my life, full-time, flat out to this. I've done my bit. I need to get on with the rest of my life."
Today the rhetoric is unchanged. Asked why he will not watch the Live Aid repeat, despite the fact that he has never once watched a video of the concert that was, in its way, a defining moment for a generation, he replies: "I've no interest in my own past at all. I'm too preoccupied with the monstrous present and with a tentative future which I do not particularly relish."
He is referring to the turmoil of his private life. His wife and partner of almost 18 years, Paula Yates, left him six months ago. It was in the emotional vacuum which followed her departure, along with their three daughters, that Geldof agreed to change his mind and go with a BBC film crew back to the death camps of the Abyssinian plateau.
Yet there is a part of him which knows that he can never let Live Aid go. Which is why there is such withering disdain in his dismissal of those journalistic revisionists who have sought to mark the anniversary with a series of articles explaining that, in retrospect, Live Aid was merely a grand and glamorous failure that solved nothing long-term, made Africa dependent on aid and destroyed what did work in local markets. "These people are just cub reporters and ex-showbiz correspondents out to make their names or sell a book."
Live Aid worked, he insists, on three levels. First, the aid directly saved countless lives; local markets were not destroyed, only local cartels that were trying to force up the price of getting the food to the hungry. Second, the political pressure that it created moved the famine to the top of the agenda in the White House, Downing Street and the Elysee Palace, forcing debates at the UN and in the European Parliament. "It prompted change in 30-odd laws governing multilateral and bilateral aid and in parts of the way that the Common Agricultural Policy impacted on poor countries," Geldof says.
But the third and most important impact it had was upon the attitudes of a new generation. "It brought a sense of - dread word - empowerment: that you weren't impotent in the face of monstrous human tragedy; that governments had to take notice of you; that there was a connectedness between you and other people; and that there were duties and obligations.
"It created something very powerful. Many people have told me that they will always remember where they were that day. Old ladies sold their wedding rings and young marrieds sold their homes. And it wasn't because of Mick and David and Tina and Freddie. It was something else. It was because romantically and improbably we had, for the first time, thrown an electronic loop around the planet and ordinary people were talking to each other."
Joan Baez at the time called the event the Woodstock of the next generation. With hindsight, Geldof sees it differently. It was not an epitome so much as a sign of contradiction. "It flew in the face of the orthodoxy of the Eighties which was characterised by money and individualism. It was a moment at which people became aware of the contrast between a world where we could throw all these satellites into space and meanwhile, below, people couldn't put their hands to their mouths. The tawdry glamour of pop did something that day to illustrate something of our embarrassment and shame and anger."
Geldof is adamant that he does not want to share in the nostalgia for that evening."What bothers me is that it infringes on my real life. In the last 10 years I've got married, had two more children, done a book, three albums, 12 singles, 20 tours, started a TV company, made money and lost money, and now been separated."
So it still rankles that people don't rate him as a musician? "I don't crave for people to see me as a musician, mainly because I know that in England they never will now. If younger people know me, it's because their teacher has told them about me in Civics. But that burden does not exist in Europe, so I can still sell a few records and tour there. It's the thing I love doing best and, regardless of what people think, is central to me. It's the only thing from which I derive satisfaction or a sense of achievement."
Geldof's other main area of activity is the TV company Planet 24, which he started with two friends and which is responsible for the Channel 4 success The Big Breakfast. "The TV company doesn't take up that much time. It's fun."
He has made a number of films for it - with Nelson Mandela, the Dalai Lama, Chief Buthelezi. "Mandela is the real thing. At last I've found someone I can't sneer about. What a man." But he leaves the detailed programme- making to Charlie Parsons and the business management to Waheed Alli and concentrates himself on ideas and long-term planning. That gives him space to continue to record and tour. He was in Germany, Austria and Switzerland for 32 gigs just before Christmas.
All that has been abandoned since his wife left him. "At the moment I can't think of anything musically." The break-up of his marriage has subjected Geldof to a new kind of celebrity: after the glitter of the pop world and the beatification of the work that brought him his knighthood and the affection of millions has come the highly public parading of the disintegration of his marriage.
For weeks he had some 40 tabloid journalists outside the house. "They were in blacked-out vans, on motorbikes tailing me, following me on foot." It has been like something out of Kafka. "You don't know what it's about or what you're supposed to have done. It seems so preposterous. You start to behave like you're in a movie, jumping into cabs and then jumping out the other side immediately and taking one going in the opposite direction. You're asked the most outrageous and hurtful things in front of your children. I feel a bit embarrassed for them, that they have such a crap job."
His tone is one of curiously unembittered resignation. "It's a condition of life. I've been in people's faces in this country for 20 years. I've accepted it, there isn't anything you can do about it, so to resist it is to completely frustrate yourself. I can't in this instance object. Unfortunately for me, I do realise it's a great tabloid story."
And so it is for a Jacobin press gleefully removing heads of the very icons of late 20th-century life - the pop star, the supermodel, the media babe and the living saint.
Bob Geldof is too chivalrous to say so, but his estranged wife has made it worse by conducting herself fairly outrageously throughout the whole unhappy business, appearing regularly in public in scenes of winsome coquetry with her new lover and disporting herself in self-parodying pin-up poses with which the tabloids have had a field day.
"I don't read any of it at all, I really don't. It would be too much misery. If you were to construct a biography from the tabloids you would create something I wouldn't recognise. But my actual life has been like a soap opera. I await with trepidation the next success or the next catastrophic failure."
All this has frozen Geldof's creativity. One musician friend has set up a little 24-track studio in the basement of his home but he cannot bring himself to use it. "It just sits there and glares at me accusingly and I have to leave the room." Eventually, however, he supposes he will do another album. And another. "I've never felt fulfilled professionally, even when we got to number one for the first time with 'Rat Trap'. Within an hour I was freaked out by what would happen next." But he cannot see himself ever giving up as he gets older.
"Age is not a factor. No one thought it stupid or undignified when Louis Armstrong pitched up at 78. What he played became the classical music of America. If the Rolling Stones can still be that bar band in excelsis with that ineffable glamour that hangs about them and Mick Jagger is a wild and beautiful animal at 52, then what does age matter? Not that I'm comparing myself to them, but I would always be happy turning up with my guitar in some club somewhere."