Secretary of State John Kerry received a letter Friday signed by 27 House Democrats who oppose the Keystone XL pipeline. Naturally, their reason is that we can’t both fight climate change and have fossil fuel development. “The math doesn’t add up,” the letter says. “In order to meet our commitment to fight climate change, we need to keep at least 80 percent of carbon reserves below ground. If the United States is truly committed to avoiding a 2 degree temperature increase, we have to start by resisting this pipeline. We urge you to reject the pipeline and keep tar sands oil in the ground where it belongs.” Never mind our economic needs. We must leave perfectly good oil in the ground so that we can fight the phantom menace of climate change. One thing about their letter is right – that math doesn’t add up.