Americans, prepare to be jealous, says Peter Madden, head of Britain's Forum for the Future. In the U.K., the two main political parties are competing to be seen as the greenest -- and the Conservatives are currently in the lead. That's largely due to Conservative Party leader David Cameron, who not only champions tough steps to tackle climate change, but walks the green talk in his own life, from growing organic carrots to affixing a wind turbine to his house (and he cuddles puppies too). Madden surveys Britain's changing political climate.