National Journal : “Over the past six years, the Keystone XL oil-sands pipeline has become a powerful symbol in the midst of a national debate over energy security and climate change. Opponents warn that construction would speed Canadian oil-sands development, which could spell ‘game over’ for the planet.”  

“But despite its iconic status, Keystone would generate far fewer emissions than the nation’s fleet of power plants … Keystone XL would produce roughly an additional 18.7 million metric tons of carbon dioxide annually compared to less-carbon-heavy conventional oil.”