You would also have a choice between different service providers such as policing service, firefighters and so on, you would chose your police the same way you chose your internet provider. Taxes are really payments to the government in exchange for services.
This is fundamentally superior than coercing the potentially wise 49% for paying for useless wars of the 51% and favors both evolution and natural selection, this neo-anarchistic approach is also trivial to implement.
It's called tax choice, where different departments can compete for your tax funds. It's essentially free-market anarchy plus mandatory contributions of XX dollars to any or all government departments.
https://en.wikipedia.org/wiki/Tax_choice
So it's one step closer to actual free markets.
OP, how about instead of straining over how to tax bitcoin so politicians can decide how to spend a large fraction of your income to pay private contractors to build roads, why not just think about ways by which roads and bridges can be built voluntarily (i.e. in the same way that cable television service, computers, cars, food, etc.. are produced) and paid for by use-fees?
But are road building projects really comparable to laying coax cable?
What is the capex of a major road building project, and what is the capex of laying cables? I'm genuinely curious to see some numbers.