The problem behind space colonisation isn't capitalism, and its ravenous search for a profit, it's because everything needs to produce a profit to be viable in and of itself. And that doesn't change whether you're running a capitalist economy, or a communist economy, or a fusion reactor, or even if you're a single-celled organism, living in a hot spring.
And it isn't about capability or energy density or whatever either. Because even if I invent a Magic Box, that I strap onto a disused grain silo and turn into a LEO cargo vehicle that can achieve $1/kg, the Moon is still an airless cinder of temperature extremes, the asteroids are still more expensive to mine than the ground under Johannesburg, and the water on Mars is still frozen solid.
Why do you want to mine the asteroids, if you can mine on Earth in a manner that is easier, cheaper, and safer?
Why do you want to build a house on the Moon, when you can build one on Earth, where you do not need to breathe air out of a tin, or huddle under five meters of regolith to protect yourself from cosmic radiation, and instead have a whole planet at your fingertips?
Why do you want to build cities on Mars, when you can already have easier living in the Namib or Sahara?
Et cetera, et cetera.
The thing is, the difference between our time, and say, Da Vinci's time, is that we know far more than we can actually implement. Da Vinci, in his quest for a flying machine, didn't think up the ramifications of heavier than air flight, for example, he didn't understand the mechanisms of flight the way the first aviation pioneers did, he didn't think up things like internal combustion so he was limited to human-powered flight, etc.
But in our time, we can grasp the physics and the math behind such stupendous and complex ideas as fusion propulsion, interstellar travel, or even the notions of such speculative concepts as wormholes.
We can figure out what a high velocity interplanetary passenger spacecraft would be like- mathamatics wise, even engineering wise, to a degree, but we can't build it, because at the current time, we don't know how.
Likewise, we can imagine the reasons for interplanetary flight, space colonisation, etc, and what those things were like.
The ramifications of say, air travel weren't fully recognised by the Wright Brothers, but even a lowly observer such as myself could describe the attributes and effects of advanced spaceflight in a far better manner.
And it really gets to the point where it's a simple problem that can be understood by any elementary school child. Even with my magic-box propelled spacecraft, it's still not worth it to mine the asteroids or colonise Mars.
In short, it isn't about how you can get into space.
It's about what there is of interest in space.
And currently, we cannot find something that is so important so as to springboard mass-scale human spaceflight. The only way we can think of such a thing- the Manned Spaceflight Killer App, is to invent some ficticious reason, a 'MacGuffinite'. That is all fine and well for your science fiction novel, but fails in reality for obvious reasons.
Look, I'm not trying to be all pessimistic here. My mind is always awash with ideas of colonies in space and on planets, with ideas of interplanetary mass transit, ideas of terraforming and other such gigantic endeavours.
But the fact that there is no known Spaceflight Killer App, means that there simply isn't any reason for any of these things. There's nothing to be gained. It should be written down as a law of nature, that if there is nothing to be gained in a process, that process will not be viable.
Nothing will help that. Not Magic Boxes, not launching ten launch vehicles to LEO in a day, not supercheap launch costs. It isn't pessimism, it's just the lack of a Manned Spaceflight Killer App.
And when I say Manned Spaceflight Killer App, I mean a legitimate Killer App. Not "x discovery and y advance will magically turn us into a spacefaring civilisation". Hoping for that is about as sensible as waiting for pink flying unicorns to establish a passenger line to Neptune.
