I am not engaging in the “food for fuel” argument. I am saying you should never depend on an unreliable source of energy, which is what ethanol is, since it is always susceptible of being destroyed by weather or pests.
It is even stupider when you start calculating the amount of reliable energy from other sources (petroleum products, hydro-electrics, etc.) that must be expended to grow this in the first place. That is, the energy needed to prepare the soil (presumably by tractors, etc.), fertilize, kill pests, harvest, etc. When you add that all up, it exceeds the energy benefit you get out of ethanol in the first place.
Same for crude oil. When you add up the energy required to locate, drill, extract and refine the energy inputs are nearly the same.