yes. 
there is the Setec Astronomy aspect of quantum computing and potential exploitation of normal network security. a scary scenario for sure... in which case we all might be screwed.... at least in the short term. 

one would think though, following that "fictional" movie pattern, that an entity controlling that capability would try to keep existence and use quite secret until at least several years of exploitation by themselves (state actors?), no?

question: even if "they" had the discipline to resist "detectable" market interference would they also be able to resist meddling with our bitcoin?

let's say it's decide to mess with the Bitcoin network...

question: what dev energy would be required to make Bitcoin network hard enough to resist Setec Astronomy?

at least for mining, after ~2,000 blocks (two-ish weeks at regular rate) the difficulty level would adjust, theoretically making the target number so small that *only* a quantum computer would be able to mine.... so maybe that would work itself out?

question: separately, what could be done to protect private keys from discovery (that's if I am understanding the implications of quantum being able to reliably work a hash backwards)?