In my opinion, Bitcoin is the ideal "money of people" not the "money of government"... no government can surveil the whole world... it has started pretty small and one by one it is huge now... what our old regime made in seven centuries, Bitcoin did in seven years.
Well, I hope you are right, kanazawa.
Unfortunately, I think that the .govs of the world could indeed kill Bitcoin, by banning merchants (anyone) from exchanging their BTC for cash. I have bought gold a few times, paying Bitcoin. In each case, the merchant instantly turns that into CA$H because that's what they need to run THEIR own business (there is a thread around, that O/P asks that we shop at merchants who do NOT exchange their BTC for cash).
The governments could just outlaw Bitpay (and similar) for example. Bitpay is who Provident Metals uses to get US$ for their incoming BTC payments. No Bitpay (etc.)? No one would take BTC, at least in my opinion.
THAT seems to be the pressure point. Who (merchants in the USA let's say) would take Bitcoin if the larger companies offering excchange of BTC into dollars were to disappear?