I don't understand all the apologism, it's pretty clear that governments can exert an unprecedented amount of control on money with Bitcoin (all your transactions are public), and no amount of burying our heads in the sand will change that.
You said the government would need to make all wallets that are not registered with some central authority illegal. That would be the same as you paying someone in cash if cash was made illegal. You would be doing something illegal in both situations. However, what is the government going to do about it if they do not know who you are?
Not to mention that making cash illegal would be a highly political issue and quite unpopular due to concerns with privacy, etc. The same would apply if the government wished to request some centrally controlled management of people's bitcoin account.
I would recommend to familiarize yourself with how bitcoin works on a technical level before mowing down more strawmen.
Also: Do you really think all countries of the world will agree on one central 'bitcoin address registry'? Contrary to popular belief the internet does not end at Virginia beach...