It's time for the annual Congressional fight over the Renewable Fuel Standard, or RFS. In one corner sit corn farmers and their representatives, who fight tenaciously not just to preserve the RFS but to expand it. In the other sits, well, just about everyone else. Whether you are a refiner, a consumer, an environmentalist, a free market economist or just someone who cares about good government, there is ample reason to oppose the ethanol mandate. Since 2005, the federal government has required that refineries blend increasing amounts of ethanol (grain alcohol) with gasoline. There are requirements for cellulosic, biodiesel and...