I'm going to go a slightly metaphoric tangent, pardon me. I like to read about un-contacted tribes and pre-modern lifestyles, and things like that. I just got done reading a sizable book on the Amazon, for example. Across the world, it seems that human society started off, or in rare cases continues to, wield deadly tools for purposes of hunting.
So when you think about it, for the majority of the last 200,000 years, all humans have lived with something like a bow and arrow very close at hand. And if they were to socially succeed, they all had to respect such tools, and they all had to know never to haphazardly threaten others with them, and their individual and tribal lifespan may have been largely based on respecting their tools and much as possible. Or, perhaps if they had a strong enough culture of respecting the tools, it wouldn't take as much effort, and the tribe would generally be more peaceful
The point is, our modern weapons are nothing but scaled up bows and arrows. If people are misusing modern tools, I might argue that no, we shouldn't have them. But we shouldn't have them, because somehow we don't understand what these newer things really are, socially and culturally. And maybe who should have them, is not understood, because maybe it takes someone who really knows how much more complicated and deadly these tools are, than older tools, for that person to appropriately have them, and not misuse them.
Again, all of our ancestors had to live with potentially dangerous tools for a long time. A very long time. Maybe we shouldn't have other kinds of tools. Why should humanity have nuclear power, if they do war around a nuclear power plant? Maybe they shouldn't have that either.