>>10862992If interplanetary colonization is possible, interstellar colonization will follow eventually pretty much no matter what.
If you can colonize Mars, you can colonize asteroids. All the same life support tech is involved, the only difference being in an asteroid you need to spin up your habitat bottle to make artificial G.
If you are colonizing asteroids, you are building lots and lots of bottle ships/stations in orbit of the Sun, which are mostly independent form one another except for minor shipments of more rare resources until they reach population cap and stop requiring any more shit except energy.
If you are building lots and lots of mostly self contained habitat ships, you can colonize the entire solar system, and your population can continue to grow and grow (even the mass of the asteroid belt alone would be enough to make enough habitats that your population could outnumber Earth's human population by a million to one easily)
At this point you have hundreds of thousands if not millions of space habitats orbiting the Sun full of people who are the descendants of Earth natives but which have lived their entire lives in space. Each habitat is self sufficient for long periods, has a population of thousands or more, and has enough industrial capability to provide products and services to those people it contains. Now, in order to do an interstellar colonization mission, you literally only need a small fraction of your total population to decide to do it, get themselves a handful of habitats plus a stockpile of additional resources, and to sling themselves away form the solar system.
In such a scenario, with a large enough fleet, this civilization could be colonizing other stars using chemical propulsion alone. It's more likely that they'd at minimum be using nuclear fission of some kind, and possibly fusion, but they wouldn't even need it.
The only way interstellar travel doesn't happen is if interplanetary colonization is impossible.
