Space is really domain expansion.

One example of an upcoming need for downmass - the ability to transport material from space to the Earth - is space manufacturing.

There are several revenue streams that are near and present that could support a private space station, including in-space manufacturing, microgravity research, and tourism - for both individuals and sovereign nation astronauts - and in-space supply logistics.

By 2030, up to 10 percent of the world's gross domestic product could be linked to space in some way.

There are items that have far superior quality when manufactured in space, but need to be returned to Earth to be purchased and used by customers.

Until space tourism is a destination-based business (e.g. flights to a private space station or to the moon), will flyers pay to fly more than once after having earned their astronaut wings? The answer to this is likely very dependent on the experience itself.