Which is the winning approach towards a worldwide currency, naturally-occurring or government-guided?

My opinion on a global currency is that it will happen and it will occur either through consensus amongst governments or amongst the global population. I'm placing my bet on the people, because our trust in government fades over time. So I think about the dynamics on which convergence to a global currency naturally occurs over a global population. I believe, blockchain technology will enable this convergence to happen naturally. Further, I don't think it will be one currency at the start. My idea is that it starts with an individual currency or token. With the bitshares blockchain, it is pretty trivial to just create a user issued asset which becomes tradeable at issuance (i.e. http://docs.bitshares.org/bitshares/tutorials/uia-create-manual.html?highlight=creating%20uia ). So at scale, say 100 million user tokens, the network metrics, especially around transaction volume would be on the basis of 5,000 trillion combinations (i.e. 100 million choose 2) of different transactions between two persons. The transactional volume on this basis is simply unthinkable. So lets start with our little Meetup. I will over our next few Meetups create user tokens for each of our Meetup participants. We need to have about 14 order of magnitude increases to see this scale. So let's start!!!!