you, TT wrote
“The US gets into a major conflict about every 80 years.
1776 US Revolutionary War
1861 US Civil War (+85 years)
1941 WW2 (+80 years)
2022 WW3? (+81 years)”
you don’t think the Spanish-American or Mexican-American wars were “major”? With the former, the USA gained huge territory in the west, with the latter it gained territory in the south-east.
Oh and what about WWI or the Korean war or Vietnam - they don’t fit in your list?
The United States has been involved in major and minor conflicts for almost the entire history since 1776.