"For the vast majority of human history, the world was full of patches of useless potential farmland—useless because the land was too far to ship from. When men and goods travel by horse or mule, let alone on foot, the shipping costs quickly exceed the value of the cargo. But the twentieth century's gradual increase in oil-powered transportation—railroads (modern railroads are powered by diesel engines), freighters, and trucks, especially—brought an enormous amount of remote farmland, once too expensive to ship from, within the reach of anyone in the city, state, country, and eventually the world. The cheaper transportation became, the more farmland came into the global agricultural economy, and the more plentiful and affordable food became." Alex Epstein