It wasn’t for a long time. It sort of is now.

The question is if, with new tech, we might be able to undo that?

But it isn't a monopoly? It is just an extremely capital intensive business. At least if you are building large passenger jets, everything else has quite a bit of competition.

What's your complaint? asteroid impacts are natural events too. I would like the government to try to avert those.

Natural monopoly is a technical term, it doesn't mean naturally occurring in the sense you're implying.

I'm sorry but you're exactly wrong. Natural monopoly means monopoly which is a direct consequence of nature, rather than through collusion and anticompetitive practice. Ie a "natural" monopoly. My analogy holds just fine.