Nature: "it is perhaps understandable that the administration, Democrats and even some environmentalists are saying little about global warming. But by failing to speak out, they have often ceded the airwaves to deniers"

A second wind for the president : Nature News & Comment

Barack Obama entered the White House on a wave of hope that was every bit as real for scientists as for voters.
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Given the toxic political atmosphere surrounding the November elections, it is perhaps understandable that the administration, Democrats and even some environmentalists are saying little about global warming. But by failing to speak out, they have often ceded the airwaves to deniers. Although polling shows that almost two-thirds of US citizens support some kind of action on global warming, law-makers in Washington DC are back to debating the validity of climate science. The United States needs leadership that is willing and able to uphold and act on the science.