The aid industry faces a dilemma. On the one hand, countries are more likely to grow rich if their citizens are provided with some important basics, such as a legal system that works, or protection from corrupt officials. Such basics might seem the priority for aid money. On the other hand, it is much easier to measure success in simpler projects, such as building roads and laying pipes.

If development agencies focus on pouring concrete, they may be spending money on infrastructure that will never be used – and perhaps never even be built – because of corruption in the background. But if they focus on the broader stuff – democracy, corruption, human rights – they risk trying to do everything and achieving nothing. William Easterly, the World Bank’s most prominent apostate, argues that development agencies love big agendas because their contribution cannot be measured and found wanting. It is a bitterly cynical view, but that doesn’t mean he’s wrong.