Sep. 13, 2012 in Project Syndicate By Bjørn Lomborg Weather conditions around the world this summer have provided ample fodder for the global warming debate. Droughts and heat waves are a harbinger of our future, carbon cuts are needed now more than ever, and yet meaningful policies have not been enacted. But, beyond this well-trodden battlefield, something amazing has happened: Carbon-dioxide emissions in the United States have dropped to their lowest level in 20 years.