Credit: Charles Dharapak/Associated Press

Few things prompt Washington policymakers to forget their professed belief in the efficiency of free markets faster than $100-a-barrel oil prices--or even the threat of them. In one of the most notable recent examples, as the price of crude oil edged toward the $100 mark late last year, the U.S. Congress passed, and President Bush quickly signed, the Energy Independence and Security Act of 2007.

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