'In the context of the 70s, when we had some sense of momentum from Apollo as far as expanding the human presence in space, it seemed like the kind of thing we could have just picked up and moved with,' Davis says. 'And it’s still possible. It’s just a matter of where we decide to spend our money." But Guidice remembers a more telling prophecy from O’Neill. "One of the most memorable things I ever heard him say was, 'If we don’t do it right now,' meaning in the next 20 years, and that was 20 years ago, 'then we’ll never do it, because we’ll be overpopulated and the strain on the natural resources will be the number one priority. We will not have any sort of inclination to see this through.'"
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