The question should be like, Can Government ban Bitcoin ? ....No, they cannot bana nything which lies outside their purview of jurisdiction. The idea of nation gives birth to the idea of government but in case of bitcoin, its an entity which isn't governed by any demography or rules except for the rules of blockchain. So No, governments cannot do much about the adoption of bitcoin by banning it but at max they can ban the usage of bitcoin for legal tenders since there is a lack of regulatory methods.