February has been the month for revisiting old and unpleasant economic concepts. Last week, financial markets experienced that 1970s feeling, as a combination of rising inflation and unemployment in the US triggered unwelcome memories of the decade of stagflation that ended the postwar golden age and the Keynesian consensus. Then came this week’s report that the United Nations’ world food programme might have to ration food aid. Set against a backdrop of rising food prices worldwide – global food prices have now risen by more than 75 per cent since their lows of 2000, jumping more than 20 per cent in 2007 alone – the news revived fears from a much earlier era, conjuring up the Reverend Thomas Malthus.

Soaring food prices have also revived some more contemporary worries. When China’s annual inflation rate spiked to an 11-year high in January on the back of an 18 per cent increase in food prices, China-watchers found themselves casting their minds back to the food price rises of 1988 and the social disturbances, protests and civil unrest that followed. Inflation is often cited as one of the factors behind the major demonstrations in 1989.