With robots producing 98% of the U.S. crop, only 2% of our labor force produces vastly more food than we need. Over 50% of the corn crop now goes to alcohol for cars, at a net energy gain of about 5%. Almost all of the rest is fed to animals at an average conversion efficiency of 13%. Soil fertility is low (half what it was a century ago) and the best land now lies under cities and suburbs, but, by adding phosphate (shipped from West Sahara) and nitrates (burned from the air by natural gas) we get fantastic yields. The nitrates eventually trickle into the Mississippi River and create a eutrophic dead-zone in the Gulf of Mexico the size of Delaware. The NOx rises from the fields into the air, increasing global warming. The profits to the CEOs of Conagra, Cargill, ADM, Continental, etc. place them among the richest 1/1000 of Americans.
We ship very little food to most countries because they are too poor to “demand” (i.e. pay for) it. The exceptions are rice and soybeans to China and Japan. As long as they can demand food, we can demand Toyotas and computers. But the U.S. is becoming saturated with Asian goods; we have a huge stockpile of unused cars and computers, so demand is dropping. For a while, Japan and China can demand payment for their U.S. Treasury Bonds in food, but that won’t last. The Limits to Growth shows a sharp discontinuity (drop) in world food/capita between 2015 and 2020, partly due to financial constraints and partly due to global warming. This year’s U.S. drought impacted all grains, cows had to be slaughtered, deer abandoned their fawns, squirrels sacrificed their young, and Texas bats suffered from a lack of insect food. Xeric plants, primarily weeds, did quite well. We should probably begin to hedge our bets by planting xeric crops such as pistachios, leucaena, and algoraba. Amaranth is the most xeric grain. Comments?