When prices rise, it is the poor who suffer most. This year's surge in the oil price towards $100 a barrel has been no exception: it is a concern for rich countries but its greatest threat is to the poorest.

The oil shocks of the 1970s were one of the roots of the developing-country debt crisis of the 1980s. Fatih Birol, chief economist of the International Energy Agency, argues that as soaring oil import bills put pressure on fragile economies, there is a danger the pattern will be repeated.