Midwestern growth also nudged the South into cash crops. Growing indigo, cotton, or tobacco is far more labor intensive than growing wheat or corn. The Midwest didn’t have the labor to pull it off, but courtesy of slavery, the South did. Each region of the country specialized in outputs based on its local economic geography, with water transport enabling cheap and omnipresent intrastate trade, generating economies of scale heretofore unheard-of in the human experience.
