Big Decisions For Future Martians

At some point, hopefully in my lifetime, we will have a permanent base on the Moon and then a permanent base on Mars and after the initial euphoria we will face a massive problem of who is in charge and who gets to make the decisions?
A team of scientists, philosophers, and lawyers have set out a template constitution for the inhabitant of the Moon and Mars which sets out principles like a 'right to oxygen' and the 'right to leave' but at some point after the human race has spread and become a permanent fixture the question would have be asked, who does the Moon or Mars dwellers answer to?
History shows that colonies tend to start resenting their owners pretty quickly (think US and UK) and revolutions happen and humans being humans there is every reason to suspect that the inhabitants of the Moon and Mars would revolt at some point.
The Blue Marble Space Institute of Science has suggested that Mars should be independent from day one and colonists would cease to be 'Earthlings' the moment they land on Mars or the Moon and would be left to their own devices until their society has built up to the point that they can establish a trading relationship with Earth.
Seems a bit harsh to just leave them alone and it is hard to believe that we could, we have never just left alone and the countries that spent billions getting them up there in the first place wouldn't want to. 
It is a problem for the future but something that should be considered because if us on Earth interfere then we could cause resentment and foster chilly relations with our newest neighbours. 
We haven't even mentioned the political and economic model that would be followed, would the supply of oxygen be run under a Capitalist system where it could be denied if payment is not forthcoming or a Socialist system where  it is subsidised and the Government provides it to everyone?
Would there be an unelected monarchy, a President making the decisions, a Government where the decisions are made by cabinet, a Corporatocracy with the missions financial backers choosing when and what is required or even a Technocracy with experts making the big decisions?   
Starting up a whole new World sounds great until you think about it and it is a minefield.