Over the last hundred years, American military and paramilitary forces, and their vendors, have subverted transparency and democracy to turn America into a military dictatorship.
There is nothing to suggest that the fall of the United States and subsequent replacement (with whatever may come) will reverse the thousand year trend of increased education and decreased violence.
The culture of the 3.6% of people who live in the current territory of the USA will be irreparably damaged, however. This may not be entirely a bad thing, given how significant an outlier the US lifestyle is compared to the rest of the world.
We're talking about long-term cycles of change here so it is difficult to opine with certainty leaving a lot of room for differing opinions. Unfortunately, however, I think the end of Pax Americana will usher in increased conflict and violence, particularly in the West which has experienced a long period of peace due to American dominance.
The US recently put the world on notice that everyone needs a larger military and should develop their own nukes if they can. I fail to see how that will continue to decrease violence.
I live in a county in which most people are armed. There are very few attempts at carjacking.
When everyone has weapons, more people get shot. That’s a fact. When countries arm up there is a much higher chance of a conflict happening that can’t be rolled back.
This is markedly untrue in most parts of the USA, including the most heavily armed ones. Almost all of the gun murders in the USA are in 3 or 4 extremely high crime (and high poverty) counties.
Dozens of other counties that have gun ownership rates 2-10x higher per capita have much much much less violence. It isn’t the guns unless you generalize entire USA to a single socioeconomic bucket.
The “more guns = more violence” narrative is simple and easy to understand. It’s also false. “more poverty = more violence” is actually correlated. Guns and violence are, if anything, loosely inversely correlated.
More people shoot themselves willingly and deliberately each year in the USA than are murdered by guns, to put it in perspective.