The American Revolution ended in 1783. The United States faced a big decision.
Would it stay a country of farmers and craftsmen? Or would it become a manufacturing country like Great Britain and France?
The northern states chose manufacturing. Within a few decades, the U.S. was right up there with Great Britain as a leading industrial nation. American factories got good at using machine-made parts you could swap easily. This became known as “the American system.”
In the South, the invention of the cotton gin made cotton a big money-maker. So the South stuck with agriculture and slavery. It had almost no industry.