The last eco-warrior to win the Nobel peace prize, Wangari Maathai (a tree-planting conservationist who won in 2004), was barely known outside her native Kenya. Al Gore is a flashier shade of green. His trophy cabinet is already bulging-the Nobel medal will have to jostle for space with an Oscar and an Emmy, all won this year. His political career has probably attracted more attention than that of any other living non-president. Billions watched the drama of Bush v Gore unfold in 2000. So last week's announcement in Norway has naturally ignited speculation that Mr Gore will mount another bid for the White House. Don't hold your breath. As Mr Gore well knows, running for president is not much fun. You have to make small talk with thousands of people you don't know. You are attacked often, viciously and sometimes unfairly. And you have to forgo that comforting extra scoop of ice-cream. Why would Mr Gore re-subject himself to such an ordeal? Currently, as the prophet of the planet's most fashionable cause