Why space colonization never happened as envisioned

Although in the 1950s/60s it seems that space colonization was only a
few decades away (see: sci-fi at the time), even if we had continued
to fund space development through private commercialization, I doubt
we'd be much farther than we are at today. Aside from the dismantling
of the rocket program and the setbacks of the shuttle program and cost
of the space station , I say we still would not be any closer to
having habitable colonies in either earth orbit, on the Moon or Mars.

Why? Simple because there would be no economic basis for doing so by
the private sector. Given the costs of putting material into space
(on the order of thousands of dollars a pound) and assembling it, no
development could be structured such that it would generate a feasable
return. Even if one could replicate a Dennis Tito scenario, that
would just mean the platform would be vanity, not a real, long-term
livable habitat.

The reason why the New World was settled in the 16th/17th century,
aside from explorations for gold, was for governments to establish
outposts for their empires and for desperate and poor settlers to
enjoy a new life away from the European millieu. By international
law, governments cannot make soverign land claims. Space presents
both high costs and a hostile environment that would be impossible for
typical immigrants to afford and have the skill to work in.

The scenario that science fiction often lays out is one from where a
group of astronauts, scientists and engineers are sent into space to
establish a base colony on the Moon/Mars. After a few years of
development the colony expands to accomodate other professions
including miners, traders, et al. Life beings to simulate Earth
communities as the early settlers being to have families on the new
planet/colony. And so the story ends happily.

However, I do not see where such an enterprise could get started in
terms of massive financial support which would run into the hundreds
of billions for at least the first decade if the settlement was going
to be an actual colony and not just an outpost. Moreover, even if it
was backed by a Bill Gates or a trans-government entity I do not see
how the colony makes a return for the investment. It is just a
sinkhole. Using the base as an exotic research center or establishing
mining operations are nice to have but they won't recoup hardly any of
the costs and any eventual breakthroughs would take many years if at
all. Unless colony can discover the fountain of youth drug or Earth
resources are so depleted that it make transplanetary shipping cost
effective, I do not see why any rational business or government would
make such a speculative investment.

For the most part, the business model that drove New World colonies
was that sailing companies would be paid by would be (voluntary)
settlers, either upfront or as a portion of their eventual labor, to
make the journey across the Atlantic ocean. The boats were often
barely seaworthy and passenger safety concerns were not a high
priority, esp. for those who paid in advance. Also the crew were
often composed of former naval men, convicts and other low paid
laborers. This model is replicated today is the cases of Chinese
immigrant smuggling.

However, each of these circumstances which made settling so profitable
for the sailing companies would not exist in colonizing space. Either
they would be impractical or intolerable. The space vehicle would
have to be custom built to exacting specifications of tolerance and
performance. The crew would be drawn from the NASA's best. If the
settlers were to be scientists and engineers, they obviously could not
afford to pay the cost there, nor bring their families. And they
would not have any means of earning any money once they landed.

So, I do not see how even the most promising developments that could
have occured since the first Moon landed would have overcome these
impediments.

Ciao.