Food commodity prices remain near historic highs. Food riots destablised countries around the world last year – more than the financial crisis – and may well return. If food was ever a soft policy issue before, it now rivals oil as a basis of power and economic security.

Like all commodities on which power depends, food is dealt in with hardening self-interest. Fearing political trouble at home, countries with surplus food have imposed export restrictions. Food-importing nations have in reaction entered large farmland leases with African states. Most of the deals are murky, many are inequitable and some are rightly denounced as land grabs.