USA Today: Not all that long ago, leading Republicans took strong positions on climate change. Sen. John McCain of Arizona, the partys 2008 presidential nominee, co-authored legislation to cap greenhouse gas emissions. And former Arkansas governor Mike Huckabee presented the fight against global warming as a religious cause. These days, its difficult to find a Republican candidate willing to speak out in favor of doing something. Anyone who does so risks defeat in GOP primaries, where ardent climate change...