In histories of the past decade, one under-recognised landmark date is August 11 2004. That was the day the International Energy Agency revised up its estimates of oil consumption in several countries, including China and Saudi Arabia, and calculated that Opec had a mere 600,000 barrels per day of spare capacity available to cover supply disruptions.

It had been clear for a while that China’s oil demand was booming but the IEA’s announcement threw a spotlight on the scale of its growth. It was a signal that oil prices of about $10 a barrel, which had seemed normal only five years before, were probably gone forever.

It also marked a revival of interest in what one might call materialist interpretations of the world economy. Since the internet boom of the 1990s it had become popular to talk about the increasing dematerialisation of economic activity, as physical products and services were replaced by information stored and processed by computers. In the words of Nicholas Negroponte of the MIT Media Lab: “The change from atoms to bits is irrevocable and unstoppable.”