TFLYTSNBN wrote:David has written that Earth had resolved its environmental crisis by exploiting off planet resources BEFORE interstellar colonization began. This is almost inevitable given that the enormous energy needed for a single interstellar ship would power our current civilization for centuries. Once you start exploiting space resources you have the ability as well as the need to build O'Neil style space colonies. Once humanity has this ability, the carrying capacity of the solar system is measured in trillions rather than billions of people. You establish interstellar colonies on habitable planets rather than in O'Neill colonies only because some people prefer to live on a planet. The former option is well described in Joan D Vinge's THE OUTCASTS OF HEAVEN BELT.
And if you watch Isaac Arthur's episodes on the possible future of the Solar System, with a Dyson Swarm (which is what Freeman Dyson was thinking of when he said "sphere", but now we use a different term so people don't think of a solid shell), the capacity for a Kardashev Type 2 civilisation in a single star system would actually be in the quadrillions, not trillions. And that's not considering virtual people, either native AIs or people uploaded.
My suspicion is that in the early centuries of colonization where ships were STL and only one way, and feasible range was limited, colonists had to settle for some marginally habitable planets. As the result, development of space resources to support a planetary colony occurred first or at least concurrently. Terraforming was probably necessary.
Which is Isaac's prediction too. You send automated ships first to begin setting up your industry, mining asteroids and such. You set up colonies either in space (more O'Neill cylinders or similar) or in low-gravity moons where you can easily take off from with launch rails or can build space elevators for with known materials. You'll have the bulk of your farming in space too, where you don't have to fight extraterrestrial microbes.
Only after you've got all of this done do you start moving people to the bottom of a gravity well. Lifting things out of there isn't easy and aid is decades to centuries away, so you to be sure you're self-sufficient by then. But he asks a question: would people want to? By this point, you've had several generations living on space colonies, possibly even having lived in other space colonies in the Sol System for generations.
For the Honorverse, we must assume that most people were still living on Earth, not in space, before departure; they made the trip in a sleeper ship, not a generational one; and setting up space-based industry at the destination was quick enough that landing all the other colonists early was a viable option.
Once FTL survey ships became available and STL colony ships became more reliable and capable, it was feasible to settle on worlds that were more habitable without significant space based industries. As long as the population is small, say less than 100 million people, the thermal footprint of your colony is not a problem. This is particularly true if your colonists are content with only a 20th century or early 21st century technology base and living standards.
Once an interstellar colony reaches a population close to one billion and desires more advanced technology with higher living standards, space industries became necessary. Space industry also becomes more necessary if your planet is only marginally habitable, toxic waste dump such as Grayson.
Why would you not want to have advanced technology and high living standards in the beginning? Why does a colony need to go through the evolutionary stage that we had on Earth: agricultural first, then industries, then space? If you're coming from space and you leave the bulk of your industries and farming in space, and you start your colony with enough people, you'll never lose your technology. You can probably have higher standard of living in a previously-unpopulated system and ready access to a lot of materials than in an overcrowded Sol System. That would be a great incentive to emigration in the first place.
