Everything else is secondary. The X-33 program should be revived and completed. SSTO is the single biggest hurdle to creating a space faring civilization. With it, all things become possible. If Bush really wanted to leave a true legacy, he should give a mandate to create, by the end of the decade, a fully reusable single stage to orbit manned vehicle. Once cheap and reliable access into space is achieved, everything else becomes so much easier.

The second big project at Nasa should be the designig of a true spacecraft. A craft that would call the ISS its home port. Whereas the SSTO vehicle would be used to ferry people and cargo to and from orbit, the explorer craft would be a strictly space based vehicle. Its purpose would be to carry people and equipment on missions of exploration within and throughout the solar system. While project Prometheus could be used to design the nuclear propulsion system, the ISS could be the place to test the crew habitation systems. When this solar system based trasportation infrastructure is in place, then Human expansion into the solar system can begin.

To do this, Nasa needs a coherent one foot in front of the other approach, not the attention deficit disorder hop scotch approach of the past. Do one thing, finish it, then move on to the next.

Lee, (Take two steps forward, pause but don't go back, then take two more steps.)