If the Democrats take the White House in November, this latest tome from Jeffrey Sachs, one of the world’s most influential economists, could easily end up serving as the manifesto for global affairs of a President Obama or Clinton. It ticks all of the right (or rather left) boxes, arguing for much more development aid, a global policy to tackle climate change and a greater concern with population growth; and it contains all the usual swipes at the Bush administration and the war on terror.

Even those who remain unconvinced by the main ideological thrust of Sachs’s book will find much to enjoy in it. He argues convincingly that much of the world, including many of today’s poorer countries, has unlocked the mysteries of sustained economic growth, a fundamental point that continues to elude many commentators in Britain. The developing world is gradually enjoying a convergence of living standards with rich nations; it is one of the greatest and most beneficial transformations since the Industrial Revolution. Sachs is equally right that a small section of the world, mainly in sub-Saharan Africa, has fallen foul of a poverty trap from which it cannot extricate itself, though he underplays just how much this is due to the disastrously flawed policies introduced by misguided or corrupt African governments.

Humanity is about to become a predominantly urban civilisation for the first time in its history, Sachs notes, thanks to dramatic progress in agricultural productivity and the remarkable economic growth enjoyed by Asia. The rise of scientific farming, including the creation of new seed varieties, chemical fertilisers, pest control, advanced