Bitcoin can not and will never be banned, because there are many ways to trade Bitcoin either online, black market, Banks, face to face etc. Government of a country can only restrict the use of Bitcoin but can not ban it. The good news is that many country that go against Bitcoin are now regretting their actions and now investing in it.
Bitcoin cannot be prohibited, as it is an international payment system that depends on each individual user of the Bitcoin network. Each individual user of this network one dealing with this cryptocurrency has a blockchain program installed, which makes him the full owner of his money and the general director of his mini-bank, which is located on his hard drive.