> So here's a question for the peanut gallery: has there ever been a large-scale public investment program into science and engineering (that ISN'T based on destroying things in new and exciting ways) that has not proved to be a good investment in the long run?
One thing that killed the SSC was an undeserved reputation for over-spending. There was even nonsense in the press about spending on potted plants for the corridors of the administration building. Projected costs did increase, but the main reason was that, year by year, Congress never supplied sufficient funds to keep to the planned rate of spending. This stretched out the time and hence the cost to complete the project. Even so, the SSC met all technical challenges, and could have been completed for about what has been spent on the LHC, and completed a decade earlier.
Leading one to believe that it was actually a good project that was stiffed by a congress in search of tax cuts. Who knows whether that's true, of course.
Does the superconducting super collider fulfill your criterias (let's forget for a minute that it is about destroying particles in new and exciting ways) ? http://en.wikipedia.org/wiki/Superconducting_Super_Collider