It is easy to mock the thousands of activists, officials and ministers flying to Copenhagen in their jets, driving around in an immense fleet of limousines, and collectively emitting more carbon dioxide than a small African country—all to force the rest of us to reduce our carbon footprints. But it is one thing to accuse them of hypocrisy in not living out their beliefs. Casting doubt on their belief that global warming poses an imminent threat to life on this planet is another.

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