The European Union wishes to take a lead in policy on climate change. This is the right end. But it must also choose the best means of reaching it. The proposals from the Commission for cutting emissions from cars seem quite unlikely to meet this test.

About 12 per cent of EU emissions of carbon dioxide comes from cars. Despite improved fuel efficiency, emissions of CO2 from this source rose by 26 per cent between 1990 and 2004. It is natural, therefore, for the Commission to seek to curb the growth.