Often we hear from bitcoin opponents the taxation argument. In a nutshell: « USD has value at least because you can pay your taxes with it. You can't do that in bitcoins. »
I'll try to forget a minute that I'm not too happy about having to pay taxes on my income, as I think there is a much less political way to tackle this argument anyway. Basically, it just consists of reminding people that the Law, and how the government works, is supposed to be something that we agree on. It is not supposed to be some external power we should comply to with no control whatsoever. It's not a force of nature like earthquakes or asteroids. It's nothing more than a convention.
Let me take an exemple. Before internet, in France there was the
Minitel. It was a neat invention for the time. It was mostly a governmental project, and as such among the main uses of this thing, were many administrative, public services, like telephone indexes, meteorology, access to public data and whatnot. And among those things, I'm pretty sure there was the possibility to declare your income in order to pay income tax.
As a matter of fact, the Minitel was so useful for lots of stuff that it was still used by lots of people much after everyone realized it should all be replaced by internet. Actually, it was still used at the beginning of this century (I personally used one to get some results of an exam, for instance).
Anyway, my point: when the internet came in, some people could easily have said: "This internet thing sucks. You can't do X with internet, but you can with the minitel." Just replace X with whatever service was available on the minitel on that time, but not on internet (believe me, there were plenty). Whoever was making that claim was right in a sense, but totally wrong in an other.
Such a person would totally have failed to understand the meaning of the verb "can". Even if some service was not available at this very moment on internet, the technological features of internet made it so clearly superior to the minitel that it was quite clear that at some point, those services would eventually be available on internet.
Now, if people really love paying taxes, and if bitcoin becomes popular enough, there is nothing, at least conceptually, preventing the government to start
accepting bitcoins as a payment of income tax.
What the government does or does not is something that
we decide. The government does not dictate the direction society should take. It should merely follows it. And to do so it often has to adapt.