I cannot imagine when bitcoin to be taxed and I think the government will search the opportunity to do this because they know that the people earn much money from bitcoin and the government thinks that they make another money if they can apply the tax for bitcoins. but I don't know if it's true or not because first, the government needs to create something to detect or to know which people that have bitcoin and I wonder how the government knows the right people that have bitcoin.
It is not easy to give tax to bitcoin users let alone from the side that bitcoin users are anonymous and can not be controlled, actually the government is very interested to legalize bitcoin so they can give tax on bitcoin users and get profit. but the problem is how does it work, to require users to pay taxes?