Most Countries issue their own currency. If a country is able to issue its own currency why should it bother taxing the people to pay for services?? A country that issues its own currency could issue enough currency to pay for the necessary social services of that country. No Tax burden is needed to pay for the necessary public services.
This is explained very clearly in
Debt: The First 5,000 Years, which I highly recommend to anyone who wants to really understand economic life (as opposed to just swallowing the prevailing
theoclassical theory).
The imposition of taxes, which must be paid in government currency, is precisely what gives government currency its worth. Even if you conduct your business entirely in bitcoin, if you live in the US or are a US citizen, IRS will still want its share of your income paid in USD. This creates great demand for an object which the government is ultimately the sole provider of, which gives it a great deal of power.