Under the Invention Secrecy Act, the US Government would be incentivised to keep encryption breaking technology (quantum) a secret, so it could hold some intel advantage. Remember this act has produced over 5.500 orders from inception. Some will have access to this info and dump bitcoin. This could the be most probable (and worst) outcome because it would create even more confusion and inertia on a much needed upgrade. You would have the dump AND no upgrade urgency. Most people agree quantum is not very good for anything else yet, so it would be the perfect target for the Invention Secrecy Act.