In the US, it feels like the 1970s all over again: high oil prices, Detroit scrambling to make smaller cars and a president urging people to save fuel by driving less. "We can all pitch in by being better conservers of energy," said George W. Bush this week.

As it happens, Americans are already less profligate with energy than they used to be: you just have to go indoors to realise. There may be a sports utility vehicle in the driveway but the washing machine, the air conditioner and the refrigerator use less power than in the past.