The line-up is astounding. While Bob Geldof generates headlines with his Live 8 concerts next month, Tony Blair will bring leaders of the G8 industrialised countries to Gleneagles to discuss African poverty. Geldof’s Live Aid did much to mobilise public opinion in the 1980s, although little to relieve poverty. This time the combination of pop stars and politicians could be truly powerful, if all stick to what they do best. That means leaving the grandstanding to the celebrities, not indulging their call for demonstrations, as the Chancellor did yesterday. And it means focusing political minds on the less glamorous, but vital, business of spending money wisely.

There is no doubting the scale and urgency of Africa’s need. More than 5,000 will die of Aids on the continent today; around 500 will lose their lives in the conflict in Darfur; about 40 million children will not be going to school next week. Such a desperate plight cannot go unheeded. The Make Poverty History campaign calculates that a child dies every three seconds as a result of extreme poverty.

Yet why should more aid suddenly work miracles, when Africa has received more aid per head in the past than any other region, with so much less to show for it? Mr Blair’s Commission for Africa has eloquently described the poor quality of much aid, the weakness of many African governments and the corruption that still mocks the poor. This makes the emphasis on doubling aid in Gordon Brown’s new “Marshall Plan” a little confusing.

The argument is that Africa has become more democratic, and that a new generation of leaders should not have to suffer the burden of crippling debts incurred by their predecessors. And there are grounds for optimism. In many of the nations that have received debt relief as part of the Heavily Indebted Poor Countries (HIPC) initiative, the requirement to publish detailed budgets and to swap debt for books and medical supplies which are easy to audit, seems to be creating a virtuous cycle of greater accountability. Hence Mr Brown’s remarks about tying debt relief to health and education, and the United States’s warming up to his proposals for multilateral debt relief.

“Africa” is not a single project. Some of its 54 countries are racked by civil war. Others deny their citizens pro-perty rights, or still dismiss attempts to audit their finances as “neocolonialism”. In such situations, it may be better to direct money to charities or to schemes such as microcredit, which loan people money to help themselves, than to governments.

All of these countries, however, would benefit from the removal of tariff barriers, in particular the EU’s corrupt and corrupting system of farm subsidies. That is a key part of the British Government’s case to G8 leaders and one which Mr Blair and Mr Brown must continue to press.

All also suffer from the scourge of HIV Aids. The proposals floated by Mr Brown for advance purchase agreements, to encourage drug companies to develop vaccines for Aids and malaria, deserve serious attention.

The first battle has been won: development aid has risen up the political agenda. But relieving poverty is a complex business. The politicians and pop stars have their hearts in the right place, but they must be relentlessly practical if they are not to disappoint those who need them most.