Science: The long and tangled history of U.S. climate politics got a new chapter this week, as the U.S. Senate today finished work on a bill that would force the Obama administration to approve the Keystone XL pipeline, which would carry crude from Canadas oil sands to the United States. Senators voted 62-36 to approve the bill, but that is short of the 67 favorable votes needed to override a promised presidential veto.
The debate over the Keystone XL bill has ranged far and wide. Senators have offered...