That is true for now, however, there are a few bills in some states that are exploring the idea of accepting Bitcoin to pay for State taxes.1

[1] https://bitcoinmagazine.com/19418/bitcoin-friendly-bills-unv...

1. Bills are introduced every session in just about every state for any crazy thing you can think of. And most of them die a quiet death, because they never had a chance to begin with.

2. States don't have their own currencies, so other than the ease of use of US Dollars, they really wouldn't care what you pay your taxes in, so long as they can use it.

That's true but not very meaningful. Imagine the difference if only US citizens would take USD (and only so much of it) instead of it generally being preferred world-wide.

So yes, a government could set up an e-currency and make us use it, but there's no way a government could (intentionally) set up a currency like bitcoin. Truly algorithmic e-currency is fundamentally incompatible with the concept of governing. Anything by a government would allow reversals, currency injections, invisible transactions, etc.

Enforcable because they have the guns

Give an example. The fiat currencies that people actually save in have a direct lineage from gold, or are linked to such a currency by monetary policy. Tax value alone has never given a new currency stable value.

> The fiat currencies that people actually save in have a direct lineage from gold

(1) What difference does "direct lineage" have? They aren't gold, and they aren't backed by gold. Unless you arguing that they have sentimental value from a historical association that hasn't been real for generations, this is meaningless.

(2) Also, this is more true of silver than it is of gold. the gold standard was sort of a brief fad (in long-term historical terms) in the final centuries of commodity currency standards as the dominant model, while silver had dominated for a much longer time previously. Pretty much all of the extant currencies that have a "direct lineage from gold" also have a direct lineage from silver, and the ones that aren't themselves relatively new have a much longer history under silver.

The direct lineage matters because my point was that it's hard to convince people that a new currency is worth something. It's easy if you promise to redeem it for something people already value.

What lineage from gold does the euro have?