When Congress threw ethanol producers a gigantic bone by expanding the Renewable Fuel Standard through the Energy Independence and Security Act of 2007 by annually increasing the amount of ethanol that fuel refiners are required to blend into the nation’s gasoline supply, they blithely made the crucial assumption that Americans’ gasoline consumption would continue to increase indefinitely. Thanks to heightened fuel efficiency and slackened driving habits, however, Americans’ demand for gasoline has actually decreased, meaning that refiners would have to blend gasoline with ethanol well above the E10 level that is considered safe for most of the older cars and...