Science fiction has always been based on this assumption. The usual premise of SF set in large colonies, those ready for independence, is that they are being economically exploited by whatever agency — governmental or private — made the original investment. The plot often involves the colonists winning, or attempting to win, their freedom. The most recent presentation of this scenario is in Firefly, which is convincing precisely because we know underneath that its metaphors express truth about the way long-distance colonization works. (Incidentally, I don’t see the situation in Firefly as parallel to the American Civil War, as has been stated in several places; politically, it’s more comparable to what the aftermath of the American Revolution would have been if the US colonies hadn’t won.) Colonies cannot be founded without a large investment from the mother civilization, which will not be made unless a return on the investment is expected; and if they provide a return, that civilization will do its best to retain control of them. I trust that in another century or so we’ll have matured enough to resolve the situation without fighting a war over it — but that doesn’t change the fact that no colonies will ever be established unless benefits to Earth are foreseen.
We tend to lose sight of this fact when we think of space colonists as rugged individualists setting out for new lands like the original American colonists or Western pioneers, which of course is a valid comparison as far as their individual motivation is concerned. Unfortunately there are two major reasons why it’s not valid in other ways. In the first place, they won’t be able to get to Mars or any other world using only their personal resources. And in the second place, they will not be able to “live off the land” when they get there, not on any planet in this solar system. Thus somebody has got to pay for their transport and their life support until the colony is well established, and whoever does so is going expect an eventual profit.
So if we want colonies, we had better hope that Earth will benefit from them, and we had better be careful about allowing the public to believe otherwise. A planet that has no resources of use to Earth will simply never be settled, unless perhaps, as O’Neill suggested, residents of orbiting colonies get so rich selling power and materials to Earth that they can fund a more distant colony on their own. It’s a sure bet that no sufficiently-large group of prospective pioneers on Earth is going to get that rich.
Then have I, a lifelong optimist, become a cynic in my old age? Since I’ve declared in The Far Side of Evil and at my website that the survival of humankind depends on colonization beyond our home world, have I concluded that we’re doomed because only self-interest can bring about the establishment of colonies? No. I believe space and/or other worlds do contain resources that self-interest leads expanding planetary civilizations to utilize, even if we are not yet aware of them or of how our capabilities will develop. I believe’s that’s a natural step in evolution (although I am not saying that all civilized species successfully take that step, or that ours will inevitably do so).
Progress is not made, and has never been made, on altruistic grounds. That is not how the universe works. Progress is made by individuals pursuing their own ends — and yet it does occur. This idea is no longer just philosophy; the evidence for it is building up through the new science of complexity (the implications of which have not yet been recognized by traditionalists) and will, I believe, transform the outlook of all sciences, including the social sciences, before the end of this century. In the evolution of organisms, communities, and even technologies — in the process of history itself — individual self-interest, pursued without regard to any central plan or altruistic aim, results in spontaneous overall self-organization (which may or may not be termed “progress,” according to one’s personal preference). Thus if it’s a natural law that at least some species that develop technology spread beyond their home worlds, as I believe it is, then it’s through this process that it occurs.