I believe lower costs come about if the government gets out of the space
business. NASA, etc. tend to make costs skyrocket (no pun intended)
because they have no incentive to lower costs and also since their
operations are labor intensive.
For near term exploitation, we really don't need a whole lot of new hardware.
This can keep development costs low. What we do need is to create a
free market in space services in the place of the current government-
business combinations (e.g., NASA-Boeing, NASA-Rocketdyne) that
dominate the space industry.
This will involve a change in the mindset of most from viewing space as
the preserve of big government/big business alone.
Without focusing solely on the technical issues, what about ways to bring
about policy changes so that the above occurs as quickly as possible?
After all, moving to space is one way to avoid any sort of the nanotech
disaster scenarios some have proposed.