Well, a country can't _really_ ban bitcoin and other crypto currency because of its decentralised nature. As longs as there is usefulness to it, there will alwa

Well, a country can't _really_ ban bitcoin and other crypto currency because of its decentralised nature. As longs as there is usefulness to it, there will always be people vying to make it a thing. The governments can collectively make it unusable - prevent all financial institutions from recognising it, and never exchange their currency to these crypto coins. This way, sure bitcoins will continue to exist, and there will always be someone stealing power to mine them, but it becomes worthless without the ability to convert to usable currencies you can buy stuff with. If BTC -> USD/EUR/etc becomes too difficult, bitcoin becomes like Monopoly money right?