Good question I think. Norman Borlaug was known for transforming places with food importers into food exporters. And to ask the question again occasionally makes sense. In recent history we are exploring the idea of vertical gardening etc. I was joking to someone once that we should grow watermelons vertically so that the large heavy melons could power a carousel style escalator or water pumping mechanism.

Not all areas are equally good at growing food. That can be because of climate, soil quality, war or simply population density requiring housing and industry.