A lot of folks believe that alcohol is a "home grown" fuel. Corn, the feedstock for virtually all of domestic ethanol production, would only be 30% to 50% as productive without the use of a lot of fertilizers. http://www.ipni.net/ppiweb/ppinews.nsf/0/7de814bec3a5a6ef85256bd80067b43c/$FILE/Crop%20Yield.pdf
It is a debate as to whether we could even meet our own food needs without fertilizers, given our current diet. But the need for fertilizers isn't really the issue. Foreign oil is.
However, we import something 80% of our NPK from abroad.http://www.fertilizer.org/ifa/HomePage/STATISTICS/Production-and-trade
Most comes from energy intensive, petro-intensive processes that are necessary to have the food/cost standard of living we enjoy here in the US.
The summary is the more we intensify domestic ethanol production to "offset dependence on foreign oil", the more we directly increase our "dependence on foreign oil". There is no discernible degree of separation between the two- one is slightly less obvious to most, that's all.
This topic is very well traveled in the energy world, and most folks who have to add up the numbers will end up rolling their eyes when politicians get involved to rant and rave about energy independence via ethanol.
Back on topic, my off-field local supplier went out more than a year ago. There is mogas on field for $0.20 or so less than avgas, and a place about an hour or so round trip sells it for about a buck a gallon less than avgas. I wish it were closer.