THE INTENTION of yesterday’s Greenpeace protest at the CBI conference was, the organisation’s spokesman said, “to stop Tony Blair delivering his speech”. Not since the author of Tarka the Otter, Henry Williamson, evangelised for the English landscape and wartime fascism has British political debate seen a more explicit identification of the ecological cause with contempt for democracy.

Some might be tempted to treat seriously Greenpeace’s objections to nuclear energy, or GM crops, while not necessarily endorsing its tactics. That is misguided. Greenpeace’s determination to shut down debate is not aberrant hotheadedness but deeply held conviction. Its is an obscurantist illiberalism more appropriate to a cult than a pressure group.

Democratic politics recognises that the things we value, such as liberty and justice, cannot all be attained and made compatible with each other. In the words of Sir Isaiah Berlin, “the very idea of the perfect world in which all good things are realised is incomprehensible, is in fact conceptually incoherent”. Economic policy deals with the central fact of scarcity, and our need to choose among competing claims to scarce resources. Most of us regard environmental protection as an important use for resources, and some rank it very high.

Greenpeace goes much further, believing that its own views on the environment are not mere preferences but moral imperatives. It short-circuits debate by declaring itself the winner, even in cases — such as its notorious campaign on the Brent Spar storage buoy — where its heedlessness of facts is no longer in dispute. Whereas the task of government is to trade off benefits against costs, including the opportunity costs of choices not taken, Greenpeace selects the benefits while paying no costs at all.

While all pressure groups are vulnerable to the charge that they advocate policy while insisting someone else picks up the tab, Greenpeace is a case apart. Its campaigning extends to vandalising GM crops and now a thuggish disregard for free speech. Another campaigning group, Fathers 4 Justice, neatly demonstrated, by hurling projectiles at the Prime Minister and handcuffing a minister, that some of its members were entirely unsuited to the responsibilities of fatherhood. Greenpeace has likewise given definitive evidence that its voice should be discounted and derided in public debate.