Ghost of Andrew Eaton said:
I'm thinking we go back to the industrialization era of the 1840s and push the factory owners to create teams. It worked for Britain and I think it could work for us. Give it time to grow and then hopefully use the Mexican American War, Civil War, and Reconstruction Era to spread it.
Football Association first rules did not* exist then and the Highway Act of 1835 in essence **** down playing mob ball with 40 shilling fines.
https://sqaf.club/original-rules-of-football/" The playing of football on public highways,[5] with a maximum penalty of forty shillings.[n 5]"
https://en.m.wikipedia.org/wiki/Highway_Act_1835The earliest formalized FA rules was 1863
https://sqaf.club/original-rules-of-football/There were many forms of mob ball with some more regulated version like rugby or soccer with the notable Dartmouth Old Division game starting in the 1830s and codified in 1871 with first written rules.
Rutgers v. Princeton on November 6, 1869 used rules proposed by Rutgers captain William Leggett based on the first set of Football Association rules I linked above. That was more soccer than not probably and the inflection point where the FA rules were interpreted as a contact oriented game without throwing or carrying the ball.
https://en.m.wikipedia.org/wiki/College_football History section
A rematch at Princeton used Princeton rules which included a free kick if the ball was caught with hands which is a feature of the original FA rules but did not survive into the game Americans call soccer but resembles the fair catch in today's American football (same Wikipedia article.)
So around 1860 to 1880 is probably the simplest way to change the story arc.