No government would be able to control the BTC money supply. To have that level of control would be like controlling the internet.
Government doesn't need to control Bitcoin on the technological level. That's exactly my point. All the govmt needs to do is make sure BTC holders have more wealth when forking to altered bitcoin sources and giving up decentralization. No majority will reject personal benefit (or the smaller loss) just for ideology.
A few months learning about bitcoin will teach people more about money and politics than twenty years studying under the present educational system will. That done, there is no going back to trusting governments and banks. It won't even be a matter of ideology.