And then, there's the unintended consequence (http://en.wikipedia.org/wiki/Ethanol_effect) of ethanol production taking crop territories and thus driving food prices up (http://edition.cnn.com/2012/08/20/opinion/mcdonald-corn-ethanol/). Which arguably causes such turmoil (http://www.economist.com/node/21550328) like the Arab Spring, and other sorts of political instability.