The biggest obstacle to Martian colonization isn't technical

Elon Musk's vowing to die on Mars has turned up the volume on the discussion of how to overcome the many daunting technical hurdles to colonizing the red planet, even going so far as to speculate about whether it is possible for prospective Martian colonists to remain human rather than evolving into a distinct species.  But there is a much more fundamental problem which has received very little attention, because merely contemplating it will make most people very, very queasy.  If thinking about torturing kittens makes you uneasy, then stop reading now because this is going to get much, much worse.

Last year, Lenny Abrahamson made a movie called Room (based on a true story, though it isn't advertised that way) about a man who kidnaps a nineteen-year-old girl, impregnates her, and keeps her and her child locked in a soundproof shed in his back yard for five years until (spoiler alert!) they manage to escape.  It is every bit as emotionally gut-wrenching as it sounds.  If you can handle it, though, it is a very good movie.  (Warning: more spoilers follow.)

Martian colonization would necessarily entail re-enacting certain aspects of this scenario.  To have a colony (rather than simply an outpost) you have to have a self-sustaining population, and to do that you have to have children.  Those children would be born, live, and die inside an artificial habitat.  This may sound cool if all you know about such places is what you see on Star Trek, but the reality of life in space is actually quite harsh, not so different, really, from being locked up in a shed in someone's back yard.  You can go outside, but only while wearing a space suit.  The rest of the time, you're completely, utterly trapped.  And on Mars, unlike the shed, there is absolutely no hope of escape.

Of course there is a huge difference in that the original colonists would be volunteers rather than kidnapping victims, but the point I'm making is not about them.  It's about their children.  They would not be volunteers.  Their situation would be similar in many respects to that of the children of the kidnapping victims.

So here's a thought experiment: suppose we lined up some volunteers to lock themselves in a habitat in the Atacama desert, and have and raise children there in the name of advancing scientific knowledge.  We'll make it a really habitat, full of cool scientific-looking doodads and other forms of stimulation.  But the children (and their parents) will be locked in for life (modulo short-range excursions in space suits), just as they would be on Mars.  If we're going to colonize Mars, we are going to have to do something like this sooner or later.

The question is: under what circumstances would conducting this experiment be considered ethical?

In all the discussion of prospective Martian colonization, I have never seen this question even raised, let alone answered.  One of the most chilling things about Room is that the kid thinks that being locked up in someone's shed is perfectly normal (because that is the only existence he has ever known) and watching the mother struggle to convince her child that it is not normal and not OK, that there is a world outside Room (they refer to shed by the proper noun), that trees and other people (besides her and her kidnapper) are real things and not just figments of her imagination.

Colonists will, presumably, have the opposite problem.  Their kids will have access to books, movies, video games, Wikipedia, social media (albeit with a time delay, so email rather than chats).  There will be no doubt in their minds that there is a world out there with other people, and that those other people get to go Outside without space suits on and see real trees and clouds and experience rain and shopping and ride bicycles and have pets.  And they will know that this world is forever and utterly denied to them because of a choice their parents made.

Except that in the experiment, the children won't really be on Mars, and that will really change the dynamic of the experiment.  It is one thing to be locked in by the laws of physics, quite another to be imprisoned by an experimental protocol.  And the whole point of doing the experiment is to figure out the psychological effects of being born and raised on Mars.  In order to do that, the children will have to be deceived.

Leaving aside the practical difficulties of maintaining such an elaborate ruse, I return to my original question: assuming such an experiment were possible, under what circumstances would it be considered ethical?

My purpose here is not to answer this question, merely to raise it, and to point out that, AFAICT, on this question the Martian colonization advocates seem to have their heads buried in the sand.  There is so much discussion about the technical and biological problems of merely getting to Mars and sustaining life there that the psycho-social aspects of having and raising children in space have been largely ignored.  (Here's a data point: "I think the biggest concern is the .38 g and how it will affect children's physiological development.")  Part of the reason they are being ignored is that the technical problems are sexy and intellectually challenging.  There's a reason that science fiction plots tend to turn on aliens and black holes rather than dealing with recalcitrant teens.  But the other reason is that I believe that once you start to really think about what it would take to figure out how to raise children off-planet most people will be instinctively repulsed by the answers.  And that may be a harder problem to solve than any of the technical ones precisely because it isn't rocket science.