I'm not sure that bitcoin will replace Dollar Soon. the government will verify, analyze & discuss hardly with the parlement before take an important decision. cause it effects to the economy, politic of the country.
Yup. There are factors that run the current fiat market that would greatly be affected if btc takes over. I don't think banks and governments would allow that to happen unless they have full control over btc, which is unlikely to happen.
The government will tax bitcoin in the future for sure because we can see that bitcoin is getting accepted in the different merchants or stores and the government will not allow that if they can't get any benefits from those stores that accept bitcoin and they can get benefit by taxing the profits in value of bitcoin that they got and that is one of the ways which the government can take place to get benefits.