This is sort of a reply to here

A basic question in regards to the space environment is how can we get anything to happened so as to get us to the point of having colonies in Space.
If we are starting from premise that we want space colonies, we might then look around space and ask where would want space colonies. You look at Mars and say that is most similar to Earth so that might be a good place to shoot for.
I would say that the reason, anyone wants space colonies is not because there is a shortage of places in which people [or that person] could live but rather it's based on the knowledge or assumption that in the future people will live in space. So the "riddle" is how are we going to reach this future. I would say that a large part of the interest regarding the space environment is related to this tug from the future- but not many people feel this pull very strongly- instead for most people it's very weak force which is constant but easily overwhelmed by other forces.

A more practicable approach is what in space is needed by Earthlings, more precisely what can we get from Space which cheaper than what available on Earth. Now, this is not a short list, but one could instead ask what is the most important things needed on Planet Earth: answer is Energy and Security- and Knowledge would trump both, but that a bit fuzzy and hard to nail down and place dollar signs on. Energy directly determines the standard of living- the countries consuming most energy are the rich countries, countries consuming least energy are the poorest. The cheaper one can provide energy the faster poor countries will become richer. More energy equals less poverty. Forget all the various ideologies, it's as simple as that. Security of course determines whether you live or die, you can mention things like freedom or how much time you might have without security, but that's really just a matter of nitpicking.

Now security related matters are already tied to Space environment.

The next question is can we get cheap energy from Space?
That is a complicated question, but if can produce energy cheap enough to sell in Earth market- less than pennies per Kw- then we will also have [or within a short time create] colonies in space. Another way to look at this is if we want to do anything in space we need to produce energy in space [satellites of course already produce the energy they need to function]. The current problem is energy production in space is costly, but this is due to cost of launching anything that produces energy [e.g. solar panels or nuclear reactors] but more important than the launch cost is there is no existing market from which someone can simply buy the electrical commodity in space- at the moment you bring your own, as though you were camping in the wilderness.

Now, there is nothing new about the idea of making large Space Power Satellite [SPS]- using the "power of scale"/specialization one could lower the high costs making and transporting electrical power from Space to Earth. Basically if you spend billions of dollars you "could" get the cost down somewhere around a buck or less per kwh or as I believe I read somewhere if launch costs could be lowered to $75 per lb it would almost be commercially viable. But if you instead approached this by looking potential markets of power in the space environment, rather than competing with the highly mature earth energy market, then one simply needs to look at ways to grow the demand for energy in space- things needed for various space activity- and as the space energy market mature it can at a later time make the big leap to the task of competing against other energy provider on Earth.

One key to growing the demand for energy market in space is mining water in space and thereby requiring energy to transform the water into rocket fuel [or propellent]. So what is needed in the space environment is cheap rocket fuel- and since going price in space is about +$2000 per lb- anything cheaper than $2000 per lb is cheap.
Therefore cheap power needed to make rocket fuel could be around $10 per kwh, and it doesn't require massive SPS nor does require the capable of beaming the power to Earth surface. Nor would such "SPS projects" compete with other NASA missions- it would instead be part of that manned effort.

Now, NASA doesn't and shouldn't need to manage and run industries which are generating power in space, or mining water in space- though it could be one consumer which buys power and water and rocket fuel- btw delivered to where they want it.
But NASA can determine if there is minable water on the moon or other locations in space. And NASA can do things that would make easier as far developing technology that would used by gas stations in orbit/lunar/maritian surfaces.