You know how that game is played. Congress is handed a schedule: this is what we're going to do, and this is how much it will cost each year. Then congress says, great, we'll give you this smaller amount. That stretches the project out and raises its cost. Congress cuts it again the next year, which raises the cost still more. This continues until congress says, look at the cost! We didn't agree to that! And they kill it.
and "promised" foreign financial cooperation was not forthcoming.
Again, that was a politically created problem having nothing to do with the machine or the physics. Japan, for example, was looking for a little cooperation from the U.S. for a project of its own (TRISTAN II/BELLE). They thought it was all worked out, one hand washing the other. Then we stiffed them and went our own way (PEP II/Babar). There are other examples, but the upshot is that our government was so uncooperative that we couldn't expect any cooperation in return.
2. The SSC was basically duplicating the work being done by CERN in Europe.
That's simply flat-out wrong. Perhaps you're thinking of the Isabelle project that was cancelled a decade or so before the SSC.
No, I'm talking about CERN's Large Electron-Positron Collider (LEP) and its Large Hadron Collider (LHC).
That's the way it goes with weapons systems.
Only with highways do they not take the final step and cancel them, they just finish them at higher cost and well after the capacity is needed.