Star Tribune: In his speech on climate in June, President Obama laid out his criteria for approval of the Keystone XL pipeline: "Allowing the Keystone pipeline to be built requires a finding that doing so would be in our nation's interest. And our national interest will be served only if this project does not significantly exacerbate the problem of carbon pollution. The net effects of the pipeline's impact on our climate will be absolutely critical to determining whether this project is allowed to go forward.'...