AP Photo

Although observers disagree about the extent, the nature and the implications of what is widely known as ‘land-grabbing’, there is no disputing that the acquisition of agricultural land in poor countries in Africa and elsewhere by rich-world actors is happening on a dramatic scale. It has been the subject of major reports by the World Bank, which identifies both opportunities and dangers in the phenomenon, and by Oxfam, which describes it as a ‘scandal’ and says, ‘The new wave of land deals is not the new investment in agriculture that millions had been waiting for.’ Why has African land suddenly become so attractive an investment option? In a continent that has gone from being a net food exporter in the 1960s to a net importer today, why this...