Ethanol and its discontents

Biofuels are going through a very rough patch lately. As recently as a year ago, smart money was betting that ethanol from corn would be the main way to reduce the global warming effect of vehicle fuels in the US: it's available, the technology is well-developed, actually much like making bourbon whiskey, and seemed to be pretty green; after all, the carbon in the fuel is taken from the air by the plants, so the only greenhouse gas (GHG) effect is from incidental sources like diesel to drive the