| America was an economic backwater until the 1900s. France was, and to a greatly diminished extent still is, a global power. French has T-V distinction. French has arbitrary noun gendering. The noun gendering alone makes it significantly easier to embarrass yourself speaking French than English. |
The US was the largest economy in the world by 1890.
It should be obvious that it wasn't an economic backwater even before that.
By 1850 it bigger than Russia, Italy, Spain, Germany, or France.
The US stopped being an economy backwater sometime in the early 1800s. Well over a century earlier than your claim.