It has been three years since the Gleneagles summit, when Tony Blair led the world’s most powerful countries in pledging to double aid to Africa within five years. Bob Geldof, enlisted by Mr Blair, provided the soundtrack to the summit with his Live 8 concerts, held under the banner of Make Poverty History.

Geldof gave the world leaders almost top marks, with an unfortunate echo of President Bush’s premature claim of victory in Iraq. “A great justice has been done,” he said. “On aid, ten out of ten; on debt, eight out of ten . . . mission accomplished, frankly.”

That endorsement did not last long, as aid campaigners mocked Geldof’s assertion, accusing G8 leaders of fulfilling the commitment by writing off debt, not giving extra money (although the countries receiving the write-offs were appreciative). In the past two years, campaigners have berated every country except Japan for increasing aid too slowly, although Gordon Brown has committed Britain to the steepest increases within the G8, which, officials argue, will enable it to meet the 2010 deadline.

In Tokyo next week, the G8 countries will reaffirm their pledge to have doubled aid by that date. But the old demand from the aid community to pledge more cash does not address the new quandaries about how to help Africa, in which aid seems only a small part of the answer – sometimes none at all. Even in the brief time since Gleneagles, the picture has become much more complicated.

The Zimbabwe crisis and the distorted Kenyan elections have been a reminder that with a malign leader, a country can shed decades of development in a year. They also show that developed countries’ levers of influence are flimsy, and getting weaker.

If there is a single factor that has changed the development project in Africa in just a few years, it is China, argues Richard Dowden, director of the Royal African Society, and a frequent critic of the belief that more aid alone is the answer to the continent’s problems. “What’s actually changed Africa are Chinese demands for raw materials,” he said. “That has brought a great deal of infrastructure – refurbishing ports, railways, roads – something Western countries have not done for a couple of decades.”

Some of that building is “on a colonial model”, as he described it – linking “the mine to the coast” – but many other people use the railway or road too. Another recent change often overlooked, he added, is the spread of mobile phones, which have enabled people across the continent more easily to find out prices, and to sell their goods.

But Chinese deals with African governments do more than just build railways. They come without strings – no awkward demands about good governance, of the kind that the World Bank or Western governments try to attach to aid. They may even bring the bonus of China’s help in keeping other countries’ criticism at bay in the UN Security Council, as Zimbabwe and Sudan found until recently. Most of all, it gives African governments a sense of an alternative suitor in any deals with the West.

That shatters the bargain on which the World Bank and many developed countries believed they were striking in offering aid: that they would pipe in the cash, and that Africans would sort out their governments. That is a problem, because in the present anguished state of development theory, the only principle that looks solid is that without good government, aid is wasted.

The enthusiasm of the Gleneagles pledges reflected the conviction by those leaders (with Mr Brown, then the Chancellor, standing close behind Mr Blair), that out of moral duty, as well as self-interest, they should help Africa – the one part of the world failing to develop, albeit with a few starry exceptions, such as Ghana.

But the Gleneagles passion was mixed with dismay, even despair, among development economists and practitioners, that half a century of effort in Africa had achieved so little in combating poverty.

A flood of books poured out from those who had spent their professional lives in that task (many in the World Bank). One of the most authoritative and least ideological was last year’s The Bottom Billion by Paul Collier, an economics professor at Oxford University. But the stream included The Trouble with Africa – Why Foreign Aid Isn’t Working by Robert Calderisi, the World Bank’s former spokesman on Africa; and assorted critiques of the bank itself.

In recent reports, the bank is willing to say only that in a certain country, a particular project worked well, with no attempt to extrapolate.

That is not to say that everything has gone badly. There is widespread praise for many local education projects, and for aid-backed assaults on particular diseases, such as the World Health Organisation’s near-miss in eradicating polio. There is, too, for efforts by Bill Gates’s foundation to tackle Aids and HIV (although some say that it diverts attention and cash from other causes).

“There has been some quite good work on conflict prevention and resolution,” argues Tom Porteous, the UK director of Human Rights Watch, and author of the recent book Britain in Africa. He points to Liberia, Kenya and Sierra Leone, and even the deal between north and south Sudan.

Britain, in its military intervention in Sierra Leone, and in mediation efforts in Kenya and among Zimbabwe’s neighbours, has played a significant role in some of those resolutions, (and Lord Malloch-Brown, Minister for Africa – after joining the Government from the heights of the United Nations – has arguably outshone David Miliband, the Foreign Secretary, in his ability to forge a deal between suspicious parties).

But as Mr Porteous argues, “when it comes to possibly the more important task of building law-abiding states . . . everyone is struggling with some very difficult questions”. One of those is population growth, that old theme of the 1960s and 1970s, which has been taboo for three decades but is rising back up the development agenda.

A conference held in Britain by the Ditchley Foundation in May asked whether rapid population growth would make the internationally agreed Millennium Development Goals impossible (many participants thought yes). Many of even the poorest African countries are managing economic growth of about 5 per cent a year, but if their populations are growing at more than 3 per cent a year, the climb out of poverty may be impossible.

The hostility of American conservatives to abortion and sometimes to contraceptive programmes; the Vatican’s influence at the 1994 Cairo population conference; a distaste among developed countries for telling poorer countries to have fewer children – all of these factors, combined with some successes in bringing down birth rates (in Iran and Bangladesh, among others), took the topic firmly off the agenda. But now it is back.

Geldof was right, for all the mocking, to say that part of the mission was accomplished: Gleneagles succeeded in extracting commitments to give more money, and the G8 countries are not so off-track that they will be unable to keep their 2010 pledges. But in the past three years, conflicts, stolen elections, and a widespread stalling of progress in beating corruption make it hard to say that more aid will bring the governments that Africans need.

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