Guardian: Three in four British voters believe Gordon Brown and world leaders are on an important mission at the climate change conference in Copenhagen, according to a new Guardian/ICM poll. Voters overwhelmingly reject the view of climate change sceptics that world leaders “are panicking about an exaggerated threat”. But close to half of the electorate believes that the leaders – including Brown, who arrives at the summit today – need to worry about economic growth, too. When ICM asked …