[JamisonM]

The "Shawcross Option" might have been for the best for all we know. The shuttle was designed to be expensive, doing things that it never really needed to do. If NASA had ended the shuttle program sooner we might very well have a better space-exploration-only vehicle out on the tarmac right now instead of... what do we have now? Oh, right, nothing. I would add that the emphasis on non-human exploration seems to be about the best possible PR and science move for NASA, it has been cheap and generated positive buzz in the media as mission after mission has exceeded expectations.