For months now, I have been hearing about something called food miles—a measure of the amount of carbon dioxide emitted in delivering food to consumers. Those who are fascinated with this approach to planetary sustainability are directed to the seemingly endless articles on this topic beginning in this millennium but strangely absent during prior eras. Was our food supply perfect during the 20th century?
Somehow someone has concluded that if we all consume food grown in our back yards or by loca…