Can Bitcoin be ban?
Yes, it's possible. Bitcoin can be banned from some countries but people who loved bitcoin will always find a way to use this. They can banned bitcoin, but the government or no one can ever stop us from using it. Even if they banned it, we will still surely use it. So banning bitcoin from countries will be useless. They can never control people.
Maybe they can not control all people, but they can do a lot that will look that way.
The influence from the governments are huge. If they create a bad image about bitcoin/crypto currencies,
and they do that for a long time,
together with regulations like:
- banning bitcoin related websites (already going on in some countries)
- monitoring all internet (already going on)
- banning VPN and TOR (already going on in some countries)
- banning all websites that accept bitcoin as payment option (to my knowledge not been done)
- making an own alternative for bitcoin that will be accepted worldwide (I guess they're working on that)
- arresting people who are dealing with bitcoin (to my knowledge not been done)
With all these things you will control the big majority of people.
Just have a look at e.g. North-Korea.
Bitcoin might become quite worthless as you can't spend it and risk will be sky high.