Obama declares he will only approve the project if it doesn't worsen carbon pollution. "Our national interest would be served only if this project does not significantly exacerbate the problem of carbon pollution," Obama says in a speech declaring that fighting climate change will be a major priority his second term.
Fighting climate change
Notable events in the dispute over the Keystone XL oil pipeline, which is slated to run from Canada to U.S. refineries in the Gulf Coast.
