Throughout history, it seems there is a huge opportunity to improve things when you can start fresh in a new place. Will we do that with Mars?
Why are we going to eventually have a Mars colony?
Overpopulation? Climate change? Lack of resources? I don't see how colonizing Mars would solve or even help that. The same technology that we would use to make Mars inhabitable would probably work much better on Earth to solve our current issues. The amount of effort and innovation required for Mars to host millions of people is massive.
As a thought experiment, though, I don't think we can even conceptualize the form of government that will Mars will have because it's so far off. Perhaps it will be mostly managed by AI
But more realistically, I think the occupation of Antarctica is a good model, at least for a century. All the big earth powers will carve out their own areas, set up labs, and put up their flags. Only when earthlings start migrating en masse, disputes may start.
> The Martian government was directed by ten men, the leader of whom was elected by universal suffrage for five years and entitled "Elon." Two houses of Parliament enacted the laws to be administered by the Elon and his cabinet.
https://en.wikipedia.org/wiki/Project_Mars:_A_Technical_Tale
I seriously hate this shit with humans dumping on other humans and I hope it ends up an AI running everything.
The treaty are nice while nobody can make a profit there. Once there is money involve, it will be back to the usual method that depends on who has more weapons there and more weapons here to defend the launching sites.
(Note that it's not always brute force and nuking. Politics is the continuation of war by other means.)