Is It a Bluff or a Libertarian Project?

Since we last talked about crypto, it's declined by more than 50%. China and russia have recently joined a list of other countries that have issued bands aimed at keeping crypto currencies out of their financial systems. I mean, all of a sudden now we have these governments interest in regulating and maybe even trying to regulate away these functions. What power do governments have to do that? Can they regulate away crypto currencies as a speculative asset? And i guess maybe more generally, what in what ways have these crypto currencies always been under the kind of pur view of government authority?