Cislunar Infrastructure

Part of building a strong economy in the Earth-Moon system will be establishing fuel depots at key points in free space.  Such stations would allow rockets to fuel up in space.

That, in turn, would mean rockets need not carry a full load of fuel all the way out from Earth, thus increasing the size of the payload, or reducing the size of the rocket.  Establishing and maintaining a system of such depots might be expensive, but in the long run, it would pay off handsomely, especially if that fuel-- hydrogen and oxygen-- were manufactured on the Moon.