Can rock change the world when it starts preaching?

SO HERE we go again. Tonight Bono, a voice of political conscience for 15 years, will be back on his hind legs with heart firmly emblazoned on designer sleeve. Backing him will be a metaphorical chorus of music- industry stars, once more mobilised for a noble cause.

The lead singer of U2, whose previous protests have opposed violence from Belfast to Bosnia, will use the occasion of the Brit Awards to take up the rather more esoteric campaign of Third World debt relief. He and the other stars are joining the demand that rich Western governments should write off debts incurred by developing countries.

To do so they are signing up behind the Jubilee 2000 Coalition, which has been plugging at the issue for three years in its current form and as the Debt Crisis Network for years before that. If you haven't heard of either, while being aware of the underlying debate, you are about to hear a lot more.

The campaign is pushing for the ground-breaking decision to be made as a millennium "gift" to the poorer nations, and for the final push is going for all the big names it can muster.

The idea of recruiting pop stars or other celebrities to a serious purpose is now de rigueur in the charity world. A number of the bigger organisations have specially dedicated "celebrity co-ordinators" to move all the high- profile muscle around to maximum effect.

But the history of pop and politics (with a small "p") has been rather more chequered than that, raising the question as to whether all the brouhaha works in the long term.

While the hippy counter- culture and its music, culminating in Woodstock, did have a huge impact on perceptions of the Vietnam War, the conflict continued for another six years.

Neither did Paul McCartney's 1970s call to "Give Ireland back to the Irish" halt what became 30 years of violence.

Red Wedge tours of the mid-Eighties failed to unseat Margaret Thatcher.

And who now remembers Rock the Vote - the music- industry attempt at mobilising apathetic youth into mainstream political action? It was only three years ago.

Then, of course, there was Live Aid, which in 1985 raised $200m world- wide and was attributed with saving a million lives in the Ethiopian famine.

With the benefit of a decade's hindsight, however, observers found it had changed little, and there was private criticism of naivety and inexperience from more established aid organisations about how things had been done.

The issues of short-termism and being seen as patronising are two of the things that Jubilee 2000 is trying to address in the latest pop-conscience campaign. All the money raised by Live Aid, they point out, is returned by Africa every week in debt repayments. "This is a mature Live Aid, if you like," said Angela Travis, spokeswoman for the organisation.

"This is not a group of Europeans saying that we can help these poor people; it is an international movement that is as active in Africa and Latin America as it is here. It is people saying to their governments and to our government, 'We want you to sort this out and do something about it'."

Claire Lewis, celebrity coordinator from Oxfam, which is part of the coalition, was in no doubt about how the music industry could raise the debt issue. "This can be seen as complex and quite turgid," she said. "By doing this we want it to become a talking-point in the pub rather than between policy people from different charities."

Some, however, worry that relying on celebrity glitter may actually be part of the problem, by encouraging a parochial attitude to the world and its problems. "It's as if we can only look at somewhere foreign though the eyes of famous British people," said Paddy Coulter, director of the International Broadcasting Trust, which is co-owned by charities and produces television documentaries on development issues.

"It is almost impossible to get another perspective on television. It is distressing that this Anglo-centricity is so strong." Whether or not the stars manage to get this new message across will itself be worth watching.