Free A Step Farther Out by Jerry Pournelle

low-growth world economy dooms most of the world's people to wretched poverty. But what has that to do with us? Can we not, ourselves, change our ways and let others go theirs?
    Probably not. Like it or not, we've got most of the technology—and we don't have enough to develop the Earth to a point of satiation. If all the world gets rich through the same wasteful processes we employed, we're probably in big trouble. Worse, what of our grandchildren? The Earth's resources will not last forever; and what then?
    I've argued here before that this generation is crucial: we have the resources to get mankind off this planet. If we don't do it, we may soon be facing a world of 15 billion people and more, a world in which it's all we can do to stay alive; a world without the investment resources to go into space and get rich. Usually I think it won't come to that; it's only in odd moments—such as when faced with The Question—that I get depressed.
    I don't think it will come to that, because the vision of the future is so clear to me.
    We need realize only one thing: we do not inhabit "Only One Earth."
    Mankind doesn't live on Earth. Man lives in a solar system of nine planets, 34 moons, and over half a million asteroids. That system circles a rather small and unimportant star that is part of a galaxy containing tens of billions of stars. Only One Earth, indeed! There are millions of Earths out there, and if we use up this one, we'll just have to go find another, that's all.
    We needn't use up this one. In a previous chapter I went through the numbers: how we can, with present-day technology, deliver here to Earth as much metal for each person in the world as the US disposed of per capita in the 60's. We can do that without polluting our planet at all, and we can keep it up for tens of thousands of years. The metal is out there in the asteroid belt. For starters we don't even have to look very hard; most of the asteroids were once spherical, large enough to have metallic cores, and now the worthless gubbage topside has been knocked away, exposing all that lovely iron and lead and tin and such we'll need to give the wretched of the Earth real freedom.
    Why not? The refinery power's there; the Sun gives it off for free. We have a propulsion system to get us to the asteroids; Project NERVA was cancelled, but the research was done, and it wouldn't be that hard to start up again. Nuclear-powered rockets would be rather simple to build, if we wanted them.
    But first we'll need a Moonbase. We can get that the hard way, carrying stuff up bit by bit from the top of disintegrating totem poles, but there are easier ways.
    We could do it in one whack Project ORION was also cancelled, but we could build old Bang-Bang in a very few-years if we wanted to. ORION used the simplest and most efficient method of nuclear propulsion of all: take a BIG plate, quite thick and hard; attach by shock-absorbers a large space-going capsule to it; put underneath one each atomic bomb; and fire away.
    Believe me, your ship will move. When you've used up the momentum imparted by the first bomb, fling another down underneath. Repeat as required. For the expenditure of a small part of the world's nuclear weapon stockpile you have put several million pounds into orbit, or on the Lunar surface.
    But that will cause fallout.
    Yes; some. Not very much, compared to what we have already added to background radiation, but perhaps enough that we don't want to use ORION—although, he said happily, ORION is one reason why I think we'll eventually do what has to be done, even if this generation fails in its duties to the future. ORION is cheap and the bombs won't go away; if we're still alive in that grim world of 15-20 billion and no space program, somebody's going to revive Bang-Bang and get out there.
    ORION gets a few big payloads to orbit or the Moon. A more systematic way would be to build a big laser launching system and make it accessible to anyone with a payload to