I take the position that after 5 billion years of meteor bombardment, plate tectonics, magnetic pole reversals, solar flares, ad nauseum, we and ethanol is barely more than a small irritant to the planet. Food is more in danger of governments and human interaction than parts if it being used for ethanol production. Neither side will be swayed by the other. Those that detest ethanol will find plenty of reasons to demonize it. Those that like it will continue to use it as long as the price makes it worth it.
The measure of integrity: Being able to see and admit the faults of your candidate as easily as those in the opposing candidate.