"I think we're a long ways from really putting colonies of people out there who would live their whole lives out there in space. I don't see that happening for quite some time."

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It is the hope of those who work toward the breakout from planet Earth that the establishment of permanent, self-sustaining colonies of humans off-Earth will ... make human life forever unkillable, removing it from the endangered species list, where it now stands on a fragile Earth overarmed with nuclear weapons. Second, the opening of virtually unlimited new land areas in space will reduce territorial pressures and therefore diminish warfare on Earth itself.

— Gerard K. O'Neill