For a setting that I'm interested in exploring
It's the standard sort of space opera setting, including a FTL drive
and the sort of inexpensive space access that makes interplanetary
trade in manufactured goods and even raw materials possible. A
standard semi-isolationist colony mission ventures to an area far from
the main sphere of human civilization and other non-human
civilizations. Over the next fifty years, the colony missions becomes
a self-sufficient, if small, interstellar civilization of a half-dozen
worlds and a quarter-million people.
At this point, random explorers happen upon a lost colony. It's a
standard lost colony, descended from an early colony mission that
succeeded in depositing its colonists but failed to sustain a
technological civilization. In the centuries since, the colonists have
gradually built a mature steady-state planetary economy, with
centuries of accumulated capital and little inclination to spend it,
although technology remains a good century behind that available to
the more recent colonists.
What happens next?
The only thing preventing the worlds established by the recent colony
mission from being satellitized would be some sort of political
decision by both parties. If the two parties are going to create a
joint economy, there is going to have to be some sort of trade and, as
our contemporary world demonstrates, it is very difficult to sustain a
free trade regime without labour mobility.
The main advantage to the the older colony would probably be access to
more advanced technology. The younger colony could profit from exports
of their technology and perhaps objects like novelty goods, or some
high-value-added products. Of particular interest might be the
availability of easy credit. Perhaps the newer colonies might have an
economic profile a bit like that of the Baltic States, with cheap
foreign credit subsidizing domestic consumption unsustainably?
Is there anything I'm missing here?


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