Of Canadian Tar sands and Obama's inbox

That is the phrase Obama's advisers have used to describe oil imported from northern Alberta's huge tar sands region, which has a far higher cost in terms of the CO2 emitted in its production than conventional oil. How much higher? That's practically a state secret, but unofficial estimates suggest that separating Alberta's oil from the sand produces as much as three times more CO2 than just pumping oil out of the ground in the old-fashioned way.

Energy independence, properly understood, is about ending dependence on imported fossil fuels because they involve shipping huge amounts of money abroad, not because the supplies of fossil fuels are actually liable to be cut off.

To the extent that the goal of energy independence encourages the growth of alternative energy sources within the US, it is a useful element in a strategy for reducing greenhouse gas emissions - but not if it is used as a pretext to replace imported oil from allegedly unreliable sources with dirtier oil from a friendlier source.