I think any NASA program started on the development of a space elevator would have to invest heavily in the relatively unknown tech of making long nanotubes. This will cost an unknown amount of money. Failures and overruns in developing the technology could doom the project. There is already Huge amounts of money going into this development in the private sector and with other government supported projects.

The best chance for an elevator concept to work it to wail for the technology to mature naturally and then take advantage of the fruits of the research.

Just physically being able to make such a structure is only part of the challenge- There will be engineering challenges that we don't have any experience with...

I am NOT dispariging the concept, quite the contrary- I just think moving on it now is premature. And reality being the way it is, if we move too soon it could doom the project...