In the coming months, President Obama will decide whether to approve the permit for the Keystone XL pipeline, which would transport crude tar-sands oil from Alberta to the Gulf of Mexico. We know that the pipeline would greatly aggravate climate change, allowing massive amounts of the world’s dirtiest oil to be extracted and later burned.

The payoff, say supporters such as the U.S. Chamber of Commerce, is a job boom in construction industries, which are currently suffering from high unemployment. Earlier this month, Chamber of Commerce CEO Tom Donohue called on the president ‘to put American jobs before special interest politics.”

If you believe headline-grabbing challenges such as Donohue’s, the president is painted into a corner on the KXL pipeline – trapped by a stagnant economy and an ailing environment.

The president knows KXL’s jobs promises are way overblown. In July, he explained it this way to The New York Times: ‘Republicans have said this would be a big jobs generator. There is no evidence that is true.” The most realistic estimates, said the president, show that KXL ‘might create maybe 2,000 jobs during the construction of the pipeline, which might take a year or two.” And after that, ‘we’re talking about somewhere […]