> The United States never has been so traumatised.
Yes it was, in the Civil War.
We recovered because our immigrants were mostly Europeans at the time seeking opportunity. They loved their new country and became Americans. They and their descendents fought in our wars against our enemies.
France’s immigrants are MoHamHeads.
I can think of no worse people group from which to draw immigrants.
I’ve already answered this in this thread: Deaths in the U.S. Civil war represented 1.9 percent of population. That is less than half that of the French in WWI.