Section 526 of the recently enacted Energy Independence & Security Act of 2007 prohibits the Federal Government (including the US military, of course) from procuring alternative fuels whose life cycle GHG emissions are greater than those from conventional sources. Might this provision have the unintended -- or intended -- effect of hindering the US military from using petroleum derived from the Canadian tar sands? The answer is unclear but the Government of Canada is sufficiently concerned that it sent the attached letter to the Secretary of Defense. Might CCS play a role? Only time will tell.