I’ve got green cards on the mind, and this brings up a potentially interesting consequence of Article II of the Outer Space Treaty (OST). Article II states:
Outer space, including the Moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means.
Discussions of the OST usually focus on what a nation state can and cannot do in space, and how they’ll interact with each other. There’s much less attention paid to individuals. When individuals do come up then Article VI is typically invoked in response:
The activities of non-governmental entities in outer space, including the Moon and other celestial bodies, shall require authorization and continuing supervision by the appropriate State Party to the Treaty.
In other words, states are responsible for what their companies and citizens do in space. But let’s flip this around. Say you’re born in Country A, but you’d much prefer to move to Country B either for increased opportunities or to escape violence or oppression. Accomplishing this is a double-sided transaction: Country A must let you leave, and Country B must let you in. Most nations today, even some authoritarian ones, generally allow the first part of this to happen, and if they don’t then escape is sometimes an option (granted, this can put one’s life in danger). The harder part of the equation has almost always been Step 2 in gaining more than temporary entry into Country B. Even the most progressive nations have exacting standards, and limit who can come under what circumstances.
Now imagine we replace “Country B” with a Mars city or an orbital habitat. The OST forbids any kind of border or sovereign claim, and a lack of borders or sovereignty should in theory mean no ability to limit immigration. One could argue such a city or habitat could still have some kind of self-governance and choose who can become part of it without necessarily establishing borders. But then Article V comes in:
In carrying on activities in outer space and on celestial bodies, the astronauts of one State Party shall render all possible assistance to the astronauts of other States Parties.
If we interpret “astronaut” here to mean any person who travels to space, then it’s unlikely that a group operating under the OST could prevent immigration to their settlement, especially if the immigrant in question is fleeing persecution or violence. Or if keeping them out would deprive them of vital consumables (namely, air). This leaves Step 1 (leaving) as the remaining hurdle, and it’s now a higher one in that getting passage to space is (at least today) much harder than scaling fences or traveling by boat or truck.
There’s also the pesky “shall require authorization and continuing supervision” part in VI. What happens if a citizen of a country travels to space without authorization? Technically it’s the state who’s in violation of the OST, which suggests states wouldn’t readily allow private actors to get to space without their knowledge. This is feasible now, but what about when space travel becomes more like air travel? Iran can’t block an Iranian living in the US with a drivers license from booking a flight.
Of course, things get messier if groups living in space try to cut ties with the nations on Earth they’re technically citizens of, and the actual enforcement of the OST in terrestrial courts to deal with stuff happening off world is always questionable. But at least in the early going there could be a period of truly open borders, offering up an expanding frontier of freedom to those who happen to be born in countries without it. In this light it’s interesting to look at Axiom’s recently announced “space program in a box”, and upcoming flights by Saudi nationals. It seems likely that some countries will face a choice in the future between falling behind in space, or keeping up and accepting a looser hold on their population.