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Physics Today has an article about what went wrong with the LANL/LLNL contract. http://scitation.aip.org/content/aip/magazine/physicstod...
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The budget has a 20% decrease to DOE office of science, 20% cut to NIH. NASA also gets a cut. This will have a huge negative effect on the ...
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Global Security Newswire U.S. Nuclear Weapons Agency to Delay Work on Interoperable Warhead By Global Security Newswire Staff February 18, ...
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There are also plans for these in which rather than being anchored, a tether could have a mass at each end and rotate about the center of gravity. This could provide artificial gravity or be used to transfer momentum to spacecraft for interplanetary travel, it would be a sort of infrastructure project again for outer space.
https://en.wikipedia.org/wiki/Space_tether
The history of tethers actually goes back to Gemini 11 in 1966, although there have been more recent experiments:
https://en.wikipedia.org/wiki/Gemini_11
It could also be used perhaps, with nuclear reactors in outer space, to provide physical separation from manned spacecraft in order to reduce shielding requirements.
What is always ignored in these talks about space elevators is angular momentum. Notice that in any launch from earth the rocket does not just lift the payload up but it pushes down range to get to orbital velocity. The same thing has to happen with an elevator. You do not just lift up, you need to get a large velocity on the payload, perpendicular to elevator and equal to the elevator velocity. You will need rocket motors and fuel to accelerate the payload to match the orbital velocity of the elevator. If you do not do this, the elevator will bend over. Angular momentum conservation. Also ignored is the question of maintenance during and after construction. You have a railroad line tens of thousand miles long and it will not be maintenance free. Then there is the radiation from cosmic rays, solar wind, and the van Allen belts. Shielding actually makes cosmic rays worse because of their high energy and resulting particle production. And then we have the damage from collisions with various space objects, including blowout from the elevator itself.
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