The net effect of a lack of a mandate is that we absolutely cannot eliminate preexisting conditions (something with near-universal support).
Maybe a Constitutional lawyer will come along and straighten me out on this, but that seems to be a clear-cut instance of regulating interstate commerce.
While I don't believe BitCoin will ever be accepted widely enough to make this happen, there are dangers if it were universally accepted.
I will admit that this is an oversimplification, but in an economic collapse, either the value of the currency falls or wages fall. Austrian school economists don't see a problem with that, but as anybody who's ever bought a more than one tank of gas in the US can attest to: prices are SLOW to respond to the reduction in the price of the inputs. Wages could fall much faster than the prices of things like food... Eventually, there will be surplus goods, causing prices to fall, but that's going to take a while. People need to eat more often than that. The logical response by producers would be to produce less, thereby employing fewer people, leading to further reduction in wages. Lather, rinse, repeat.
On the other hand, if a government can devalue its currency in one fairly dramatic step, you create a situation where goods are temporarily cheap, causing people to consume more. Eventually, the prices of the inputs will go up, and the goods will become more scarce, but if you can borrow consumption from the future, you can head off the feedback loop. This has been used to good effect in the past.
If everybody were paid in BitCoins, devaluing a national currency would be ineffective at heading off a recession, leaving few tools in the toolbox.
That's no reason not to treat the "symptom", too. People respond to incentives. If you make the disincentive against piracy stronger, there will be a reduction in the number of pirates.
The problem lies in what the remaining pirates do to make it worth their while. They could become more violent in response, because they need to extract more money to make the extra risks worth taking (which could be a reason not to treat the symptom). It's also possible that the whole endeavor becomes too risky to make it worth doing... There's really no way to tell in advance. My hope is that no matter what they do about piracy, that they are wary about unintended consequences.
Quark! Quark! Beware the quantum duck!