Janet Street-Porter: Why Geldof makes me want to scream

Make no mistake about it: Live8 is the marketing moment to end them all

This will be remembered as the year pop music finally lost any credibility it ever had. It's been a gradual process, with the long and winding road from Bob Dylan's protest songs of the 1960s finally ending up in 2005 in the car park of good intentions and zero content. Dylan's autobiography was a fascinating chronicle of a committed young man devoting his life to music he found inspirational, a story of long nights in clubs playing with folk musicians who truly believed their music reflected the American underclass.

This will be remembered as the year pop music finally lost any credibility it ever had. It's been a gradual process, with the long and winding road from Bob Dylan's protest songs of the 1960s finally ending up in 2005 in the car park of good intentions and zero content. Dylan's autobiography was a fascinating chronicle of a committed young man devoting his life to music he found inspirational, a story of long nights in clubs playing with folk musicians who truly believed their music reflected the American underclass.

An excellent series on BBC2 at the moment, entitled Soul Deep, has been essential viewing for anyone interested in the era when black music spoke directly from the heart, untainted by marketing and glossy packaging. In the mid 1960s, Otis Redding, Percy Sledge, Aretha Franklin and Marvin Gaye were revolutionary artists, changing the landscape of popular music forever, bringing the hopes and aspirations of black people into the mainstream, giving them a focus and an identity in a way that has never been equalled.

And what has happened to these inspirational black and white session musicians and singers? Many are penniless, having received few or no royalties. Even though their talents are as undimmed as ever, they've been thrown on the scrap heap by the music industry because they're not in fashion. Interesting that it takes a white middle-class organisation like the BBC to set out to chronicle the hollow vacuum that now exists at the heart of American music.

It's ironic that pop music believes it is an appropriate conduit to "save" Africa, to make us aware of poverty and debt, suffering and injustice. Pop music in the 21st century is also the industry of conspicuous waste, a business so obsessed with the next big thing that every week young men and women are routinely hyped up and then dropped when they don't fit this year's marketing strategy.

The music industry is run by a handful of businessmen who place zero value on long-term creativity and nurturing talent - how far have we come from the days of Stax records in Memphis, Tennessee, where local blacks and whites worked together to come up with songs that truly changed the world?

As Bryan Harvey, formerly of East17, lies critically ill in hospital after an apparently self-inflicted motoring accident (having previously tried to commit suicide), let's not forget that he's a terrific example of a young musician built up and then dumped when no longer regarded as flavour of the month.

These days talent is sifted via prime-time television series, signed up in response to viewer reaction, styled and marketed in order to offend as few people as possible. It's about as threatening and revolutionary as a Big Mac. Punk seems like a brief, dim and distant period of shock and innovation.

Today, musicians can't just make revolutionary music, they have to have opinions on everything from human rights to global warming. Pop groups are always droning on about environmental issues - and yet they set an appalling example of waste. Recently Thom Yorke from Radiohead was used by a Friends of the Earth campaign to make the government reduce carbon dioxide emissions. Along with many other groups from the Rolling Stones to Atomic Kitten, Radiohead have promoted carbon neutral touring, planting trees for every concert-goer. But the reality is that using jets and cars when embarking on lengthy world tours more than neutralises any good done by planting a few trees.

Chris Martin from Coldplay (another self-important environmental whinger) and his wife Gwyneth Paltrow are said to drive the Toyota Prius, an eco-friendly car so trendy there's a two-month waiting list. Shame, then, that Mr Martin also uses private jets to meet up with Gwynnie and the baby while on tour promoting his new album - I suppose he justifies that in some convoluted way as "essential".

Pop stars should get on with what they are good at, making music that brightens up our lives, gives us something to dry our hair to, wipe the baby's bottom to and play on our iPods to get through the horrible journey to and from work. Pop music can enrich our lives and give us moments of great happiness. But when Sir BobGeldof, no matter how sincere, tells me that a concert in Hyde Park is going to help raise awareness of poverty in Africa I just want to scream.

I know about malnutrition, rape and suffering in Africa, as does anyone with half a brain cell. What we also know and despair of is Africa's inability to deal with corruption, to put its own house in order, to end the shameful raping of innocent women, the mindless religious wars, the conscription of child soldiers, the selling of children into slavery, the widespread lack of rights for women.

Ordinary people already respond to disasters and deprivation whenever they are asked, on a scale that governments do not. Only last weekend we heard stories of how little of all the billions sent to Sri Lanka to help the homeless had actually got through to the needy. Instead of building 9,000 homes only a 100 had gone up, as bureaucracy and red tape prevented aid from reaching the needy. Too often, our donations are stolen by corrupt officials or milked by administrators and consultants.

The list of artists announced on Wednesday reads more like a roll call of the bland, the acceptable and the old pals than anything else. Annie Lennox? Maria Carey - the woman who issues demands about what side she can be photographed from, who wants red carpets on pavements, dozens of candles in dressing rooms, who is known as the nightmare diva to end them all? What constituency of pop does she represent other than conspicuous consumption?

Elton John spends a huge amount of time raising money to help Aids sufferers in Africa. He also gives a huge chunk of his income. For many of the people listed in this line-up, however, it's a chance to get on world-wide television, sell a load of albums and feel very pleased with yourself at the end of the day.

The Spice Girls re-forming? Geri Halliwell's recent efforts to promote herself via a television documentary and press interviews have been widely derided as shallow and self-seeking.

Make no mistake about it, Live8 is the marketing moment to end them all - and that's why most of the people on the list are those who are already easily recognisable brand names, relentlessly marketed on a global level. I thank them for giving up their time. I recognise their good intentions. But ultimately they won't make any difference at all.

Finally, have Silvio, Tony and co agreed to give a month's salary to the cause, to forgo the use of private jets? I doubt it. The only way to impress African leaders is for our own statesmen to set an example - unfortunately, a bunch of pop stars impressed with their own self-importance will have less impact.