Replying to the reply to my parent comment, since I seem to have reached HN's nesting limit.
Forms of control are not always very direct. Let us, hypothetically, say the big state actors jump in to take control of 80% of the available bitcoins available, under various entities, they have control and authority and little accountability.
This is already a reality in some equity markets, where retail investors are under 20% and rest of the players are institutional players. It will take much lesser than what it takes to move a large equity market, to move BT.
There is a good reason why there is no global barter system. It simply won't work at that scale. A global barter system -- that would be truly subversive.