For now I think it's going to be tough if want to ban bitcoin, because bitcoin communities are big enough in the world and bitcoin users also feel good results from bitcoin because bitcoin has good potential in the future, so chances are if bitcoin is banned then this community will move for fight it. I personally would not agree if bitcoin is banned, we must maintain the existence of bitcoin in this world.
let me add that bitcoin is not something illegal and harmful to be banned. Bitcoin is a technology that that was made to make transactions simpler and more innovative.