Forbes: Pity the American farmer. Now, if Senators Klobuchar and Grassley are to be believed, they have been the victims of monopolistic behavior by the oil companies, who are limiting sales of ethanol-enhanced gasoline by requiring gasoline stations to carry premium fuel. At the same time, the New York Times is reporting that some believe that large Wall Street firms have profited from trading ethanol credits, driving up their cost. So, we have banks against the oil industry against the farmers, apparently....