This isn’t really a surprise to anyone familiar with him and his history, but Newt Gingrich is continuing to promote prizes for space achievements. I agree with commenters that his proposal of twenty billion for a human Mars mission is a prize too far, not just for all the reasons stated (too much money to raise privately, too long-term a proposition, too little faith in the government to keep its word) but also because I’m not sure that there would be adequate public support for the goal itself. A more incremental approach is indeed required–going from a ten million dollar prize to a twenty billion dollar prize is just too much of a leap.

I also agree with this comment, with a caveat:

IMO, we should start with smaller prizes. I would create three (3) prizes, in the following order: 1) orbital RLVs, 2) LEO propellant depots, and then 3) Processing oxygen on the Moon, and 4) Delivering the oxygen from the lunar surface to a LEO prop depot.

I suspect that it will be a long time before it’s economically viable to deliver lunar LOX to LEO, at least directly. What I would envision happening is a LEO depot, an EML1 depot, and a continuous parade of low-thrust tankers (which might also serve as the depots themselves while in place) moving back and forth between the two locations, delivering propellant to wherever the price dictates. If the tankers could deliver lunar LOX to LEO at a lower cost than delivery from earth, then they would do so. If it only made sense to use lunar LOX one-way as propellant to leave the moon, and it was cheaper to refuel at EML1 for the return using LOX delivered from earth, then that’s what should happen. The important thing is to establish the propellant supply infrastructure, regardless of the source of propellants. Building roads and a gasoline-delivery infrastructure was critical to making reusable cars (as opposed to the one-way Conestoga wagons) practical, and we need to do something similar in space.