Today more than 60 countries gather in Paris to consider Afghanistan’s request for $50 billion (£25 billion) to try to haul itself out of the ranks of the world’s poorest and most dysfunctional states. And today the Irish Republic, which has turned itself in 40 years from one of the poorest countries in Western Europe to the second-richest, much of that with European Union help, votes on whether to approve the new, unifying EU treaty.

The comparison between their experiences is made explicitly by a superb new book, Fixing Failed States, inspired by the world’s struggling efforts to help Afghanistan. The contrast goes to the heart of the question of why some poor countries get rich and of whether failed states — the most broken — can be helped at all.

This is a curious point in the history of rich countries’ efforts to help others. The world has never been so good at generating wealth and investors are increasingly tolerant of the risk of unstable places. That is one of the arguments for optimism made in this book by Ashraf Ghani, a former Finance Minister of Afghanistan and Clare Lockhart, a lawyer with five years’ experience of trying to build Afghan institutions in Kabul.

Foreign aid is still a popular cause, at least in Britain. Gordon Brown and Tony Blair each made clear that African development was a personal passion but they were also shrewd about the valuable constituency to which this appealed. Except that, 60 years after the triumphant reconstruction of Europe, there is little agreement about what works. The World Bank is reduced to terrified agnosticism in many reports, willing to venture only that, in a certain country, at a certain time, some policies have helped.

As Ghani and Lockhart point out: “In the past 20 years $300 billion has been spent in Africa alone yet the continent is still rife with weak and collapsed regimes — two million people a year are dying of Aids, three thousand children die every day of malaria and 40 million receive no schooling at all.”

Ireland shows how fast a country can change when a government makes thoughtful use of aid. It has done that arguably better than any other EU recipient, to turn itself into the fourth-richest country in the world, measured by gross domestic product per head. Ghani and Lockhart attribute this to intelligent leadership in recognising the value of its location between the US and Europe, of an educated workforce and of the opportunities in the EU market and the internet revolution. Crucially, it also had the developed institutions to make use of the aid. It is patronising to suggest, as France has done in the past week, that Ireland owes it to the EU to vote “yes”; that ignores Ireland’s central role in its transformation.

Ireland is not alone, the authors note, in a second point for optimism. The past few decades are rich in examples of rapid development. The mistake in too much development effort, the authors argue, rightly, has been to be so respectful of sovereignty that countries are prematurely treated as if they are fully functioning states when they lack the apparatus to make the best use of aid.

That was true of the World Bank in Africa and it is now true for Afghanistan. Donors have been inclined to treat it as if it is well on the way. But it lacks most institutions and has too many people high up who appear hostile to their creation for fear of diminishing personal influence. The task of the Paris conference is to ask the leaders of Afghanistan what they are doing to repair this gap before handing them more billions.

— Fixing Failed States – a framework for rebuilding a fractured world. Oxford University Press. £13.99 pp254.

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