I would like to point out that the only reason a space elevator makes sense is due to the inefficiency of current rocket engines and the total costs (environmental and energetic) of producing rocket fuel. Space elevators purpose is just to reduce the price of delivering loads to orbit.
In case we have cheap energy and/or reaction-less drives and/or cheap easy to produce environmentally friendly fuel (aluminium rockets are being tested now) space elevator becomes more of a attraction than practicality. Yes it would be nice for kids to take an excursion to, but in case you could buy semi-orbital flight for ~1000 usd, it becomes less of an interest.
