Bitcoin rely on a decentralized Blockchain, that cannot be shut down by their local governments. 
Governments can't indeed do anything to stop Bitcoin. However, if they so wish, they can force mobile network providers, ISPs, and all other related companies, to cut all ties with Bitcoin and any activity that comes even close to it. On top of that, they can force through all kinds of outrageous policies and punishments for companies not abiding their law. It may sound as an extreme situation, but the majority (if not all) of the countries in the continent of Africa are severely suffering from corruption. So in that regard, it's perhaps a realistic scenario if Bitcoin grows too large in these countries.
