Now that the credit crunch and high food and commodity prices have come along and seem here to stay, David Cameron’s Conservatives, according to the British historian and commentator Max Hastings, would be wise to drop all their high-minded guff about the environment. In belt-tightening times there are other priorities. The signs are that Labour’s very modest increase in fuel tax and proposals to raise excise duty for the most polluting cars may fall victim to protests against tax rises which, presumably, no-one ever imagined would be popular.

On the other side of the Atlantic, in the most dramatic presidential nomination campaign in living memory, the environment has barely figured at all. Hillary Clinton’s image as a tough pragmatist does not accord with any sort of greenery, and in Barack Obama’s glowing vision of a new politics and peace on earth, the environment is strangely absent. It is left to the elderly war veteran Republican candidate, John McCain, to be an unlikely upholder of ecological values.