New York Times: As President Obama prepares to complete sweeping regulations aimed at tackling climate change, at least five Republican governors, including two presidential hopefuls, say they may refuse to carry out the rules in their states. The resistance threatens to ignite a fierce clash between federal and state authorities, miring the climate rules in red tape for years. The fight could also undermine Mr. Obamas efforts to urge other nations to enact similar plans this year as part of a major United Nations...