[hollerith]

The US was the second country to industrialize (Britain was first; France third) and that industrialization had been going very strong for many decades before the start of the American Civil War. Also life expectancy, infant mortality, adult height and similar measures were better in the American colonies than in the most advance Western European countries a century (and probably a century and a half) before the start of the Civil War. So I don't agree that it was a 3rd-world country at the start of the Civil War.

(I have no opinion on grandparent; I am reacting only to your choice of the term "3rd-world country".)