I read a book called The Long Emergency last year and it was an excellent analysis of the worldwide oil situation and what we can expect in the future. One of his points is that when, not if, but when we run out of oil, we are suddenly without not just fuel for tractors and other farming implements and international food shipping, but also plastics and pesticides and whatnot that are also petroleum based. Figures show that pre-oil glut, using traditional farming methods, the Earth could produce enough food to feed about 1 billion people. With oil, we're feeding close to what, 5 billion? So when the excrement hits the air-conditioner, we suddenly have about 4 billion too many mouths to feed. The "I ♥ My Carbon Footprint" people will be the least prepared and the most guilty.