Some media shows that bitcoin can be the next weapon to control the world economy. i think it is true and it will be seen soon.
For now I think it is not possible. It's influence is not wide enough that we could say that it will have a large impact to the world's economy if there is a price movement of bitcoin.
As far as i know bitcoin is using legally in many countries especially in my country every person is now using bitcoin there's no restricted from government side.