"Nitrogen made from and by the petroleum industry" This is it. When growing food, soil and labor are not the limiting factors. Petroleum is. If you have lots o

"Nitrogen made from and by the petroleum industry" This is it. When growing food, soil and labor are not the limiting factors. Petroleum is. If you have lots of oil, you can perhaps do hypdroponics in a desert; if you don't, all your farming will need heavy subsidies to cover for its petroleum consumption. I don't expect world to care about soil until it becomes limiting factor. Call me when they resume growing grain in Siberia.