Anthony G Williams
Greybeard
If the principal reason for establishing a colony off Earth is to provide a back-up in case a giant asteroid strike or something wipes us out, then by definition the colony has to be self-sustaining.
It is by no means a given that human science and technology will continue to develop. Our society is very interconnected, as you note, but that brings its own vulnerabilities. A lethal and highly contagious disease could spread around the world extremely quickly (especially if it has a long incubation time). If people stopped turning up to work for fear of catching the disease this could rapidly cause the progressive collapse of our society. Other possible causes of disaster might be a serious (but not extinction-level) asteroid strike, or simply huge shifts in the global climate caused by a runaway greenhouse effect. Any of these could shatter our fragile interdependence and lead to a death toll in the billions.
If anything like this happened, while humanity might survive it, the technology level would probably be much lower. Just think about what it takes to make the PC on your desk - the rare minerals mined from all over the world, the sophisticated chip production techniques concentrated in very few factories in other countries, and so on. Making that computer involves a high technology functioning via a complex international web. Break that web and how do we make computers?
Furthermore, once we lose our advanced technology we can probably never regain it (at least not in its present form). All of the easily obtainable minerals and fuels have already been mined out. To get at the rest we need very high-tech methods (e.g. deep ocean drilling for oil). So without that technology we couldn't get at them...a post-catastrophe human civilisation would probably have to be based on wood, not metal!
It is by no means a given that human science and technology will continue to develop. Our society is very interconnected, as you note, but that brings its own vulnerabilities. A lethal and highly contagious disease could spread around the world extremely quickly (especially if it has a long incubation time). If people stopped turning up to work for fear of catching the disease this could rapidly cause the progressive collapse of our society. Other possible causes of disaster might be a serious (but not extinction-level) asteroid strike, or simply huge shifts in the global climate caused by a runaway greenhouse effect. Any of these could shatter our fragile interdependence and lead to a death toll in the billions.
If anything like this happened, while humanity might survive it, the technology level would probably be much lower. Just think about what it takes to make the PC on your desk - the rare minerals mined from all over the world, the sophisticated chip production techniques concentrated in very few factories in other countries, and so on. Making that computer involves a high technology functioning via a complex international web. Break that web and how do we make computers?
Furthermore, once we lose our advanced technology we can probably never regain it (at least not in its present form). All of the easily obtainable minerals and fuels have already been mined out. To get at the rest we need very high-tech methods (e.g. deep ocean drilling for oil). So without that technology we couldn't get at them...a post-catastrophe human civilisation would probably have to be based on wood, not metal!
