Hi

Very true and succinctly put. One threat to that time-scale is our present resource bickering which will only get worse if zero-growth economics gets overly promoted by social radicals. The worst outcome is the rise of a "Static State" ideology, perhaps in the wake of a resource war, which will kill any hope of space development.

Humans need to grow beyond the range of geophysical and astrophysical threats before anyone can reasonably advocate "zero growth". If people knew the urgency of expanding the in-space economy before the economic necessities of a finite planet kick in, then we'd have a serious motivator.

I'm heartened by a recent opinion piece by Stephen Gillett in "Analog" that a lot of the old space economy "necessities" (asteroid mining etc) might be made redundant by nanotechnology - the use of bio-mimickry to concentrate and even refine minerals will make a lot of large-scale mining/resource operations pointless. And the distributed manufacturing promise that is offered by rapid prototyping technology - especially "self-reproducing" rapid-prototypers - will eventually enable advanced industry to be located anywhere and made immediately responsive to community needs. We are on the verge of a transformation of industry that will provide the tools for rapid expansion into space.

Adam