See this for the whole discussion thread: http://waitbutwhy.com/table/mars-government
After reading through a whole library worth of opinions on the topic, I submitted this:
Flame war on true democracy / capitalism / realism vs utopistic / communistic / idealistic ideas seems to be over quite soon, so now my 2 cents.
I think no matter what kind of government we think will be created on Mars, it’s not going to be the product of any person on Earth, either us here in this discussion thread, or anyone else (Elon Musk and all politicians included). What I can rather imagine is some sort of emergent development of political system, rules / laws and enforcing of those. Only those rules are more than fantasies that have a way of being enforced. So the question of how rule / law enforcement will happen there is at least as important as what these laws will be or what decision mechanism will be used to create these laws. Why am I saying this? Because humans are fallible, and unless we want only robots to colonize Mars instead of people, things will be randomized by different points of view, mental issues or just simple lust for power (as properly discussed below), so things will go wrong, and there have to be ways of making them right again.
So let’s imagine John Doe, early Martian decides to play against the rules (at this stage probably defined by a not much more sophisticated mechanism than corporate hierarchy of SpaceX or NASA or whatever), or just thinks he can create his own rules hurting most of other Martians’ or the Company’s interests or points of view. While the colony is in its early stage, probably there will be very few people who absolutely rule out the possibility of getting back to Earth at a certain point in time, so as a first wave of enforcement, just the threat of “when you get back to Earth, you’ll be called to account for what you’ve done on Mars” will properly do.
Then, when enough people (either absolute majority or a large enough aggressive minority) will be like “I don’t go back ever” (and probably the Mars colony being somewhat self-sufficient and able to defend itself from being challenged by an “enforcer” spaceship sent from Earth), they will start demanding or creating their autonomy or power over the rest of the colony. Then it will somehow, probably through a step-by.step gradual process, result in a goverment model that is impossible to either predict or influence from Earth.
Finally, probably in an even later stage, when there will be already 2nd, 3rd etc. generation of Martians who are less idealistic, super-educated, motivated, whatever, than the 1st generation, people will start showing up who either just can’t weigh the consequences of what they do or they have nothing to lose, and are willing to cause real damage to other Martians or the whole colony. Then, the key question will be not only how to enforce certain rules or laws, but also how to proactively prevent big catastrophies from happening (as the Mars colony will be very vulnerable). Therefore, both passive and active protection of key infrastructure pieces will be necessary. Passive like redundancy and robustness, and active like guards, security systems etc. I think this need for protection mechanisms is more or less independent from the form of government or how it changes, so it should be something like the very core of how Mars is operated. Similarly to the 3 laws of robotics.