The history of the world, is more honestly written with the formal acknowledgment that it is might, rather than right, or any other sort of cause, noble or not, in which revolutions are successful and governments are thereby duly formed. Sure, there is such a thing as a peaceful revolution, or even a peaceful transfer of power from one form of government to another, but most governments are actually formed through force, above all. So then, in recognition that soldiers need to be an integral part of that armed revolution, they are thereby suitably provided with arms and training so that they can best perform their necessary duty.
In sum, upon the success of a given armed revolution, and once that new government is successful in being formed, those soldiers previously used, but no longer really necessary in the day-to-day operations of that government -- necessitates that the armaments previously held in their hands, will and must end up being returned to that government; so that, only those that are considered to be the most loyal to that new government, will thereby be permitted to remain armed. What most governments do not desire to have, is exactly the problem that America best represents. We read at statista.com, that it is estimated that the "...U.S. had 393.3 million civilian and illicit firearms in 2017," which thereby is a significant reason why America has so much civilian violence as well as a material fact to keep in mind, that should the people rise up with arms against their own government, such a battle as that, may well be protracted, bloody, and seemingly endless; of which, this internal fighting would end up costing many lives, on all sides, and would probably last years upon years. In other words, most governments so formed through violent means, make it a point, to take back those arms from such of those that because of their class or because of their background, might well be considered to be of questionable loyalty; and thereby allow only those to keep arms, as well as its most powerful weaponry, of those that are not conflicted as to where their loyalty must so properly lie.
So then, in consideration that those that are armed, always have the advantage over all those who are unarmed; governments, the world over, have demonstrated a strong tendency to disarm the general public or make it their abiding purpose to do so; and in particular, to try to keep armaments away from those that have a minimal footprint of status within that nation, and therefore aren't particularly trusted by that government. When it comes to America, we find that throughout this nation, that the general population is insanely well armed; though, of course, their fire power and accompanying protection, thereof, is significantly weaker than the policing and military arm of the state. That said, the general public is indeed, quite well armed, which pretty much entails for those that see themselves as being effectively disenfranchised, that though they are often without material assets of significance, and don't have a lot of good cards to play, that they do still have one, and that one, could well spell the difference between authoritarianism or the continuation of some reasonable form of democracy.