Has anyone looked at the USAF project called Dynasoar?
It looked like a smaller version of the Shuttle.
Dynasoar died because of arms limitation treaties.
No, it died because there was no clear mission for it and it was very expensive. It was too small to be very useful as an actual spacecraft, didn't have much payload anyways, and just plain didn't do anything that other, cheaper systems couldn't except "explore aerodynamic reentry". Which is not much of a justification for a billion+ dollar program in the early 1960s. So McNamara killed it.
There weren't any arms limitation treaties that could possibly have affected it (even if it was designed to carry weapons, which it wasn't) until after it was cancelled, anyways.