I suppose that ultimate control will lie with whoever owns the most resources, and how badly those people want to come back to Earth. If you have more carrots

I suppose that ultimate control will lie with whoever owns the most resources, and how badly those people want to come back to Earth. If you have more carrots or sticks available to you on Mars than other people there do, then you can influence them, making you the de-facto ruler. If you declare yourself supreme leader of Mars and then go kill a bunch of people, when you land back on Earth for your friend's cousin's grandma's birthday party, you'll just be arrested. Realistically, corporations will probably get to Mars first, but governments won't be far behind. I would recommend keeping your rage-killings to a minimum for that reason. I don't think you have to go to Mars to do this. Many factions have claimed convenient islands on Earth as their own and have built highly functional societies even though other entities claim that they're the actual government. But of course, those societies watch the power struggle very nervously. If you can do it 80 miles off the coast of China, you can probably do it 230 million miles away.