"But unlike three hundred years ago, when elsewhere was America, there is no elsewhere nowadays, it's all booked up, full."

At some point in the future there may just be the possibility of moving on and destroying a few more planets(opposed to just continents) when we've tired of this one ... Why else do you think so much money is thown into space exploration - surely it isn't to 'learn' anything new. No-one seems to be too keen on 'learning' from past lessons(history) so i can't think why the future holds any more appeal with regard to learning....