El Salvador makes Bitcoin legal tender

Certainly not. I never claimed it was. Neither can cement, cars, porcelain, or most other products of heavy industry. Aluminum is an exception here.

> a future where mining is constrained by geography and friendly states absolutely obliterates any decentralization

I'm not sure what kind of future you're imagining here. Are you thinking that maybe Algeria will monopolize world bitcoin mining because it has 0.1% more sunlight than Chile and Saudi Arabia, so its mining costs will be 0.05% lower? That seems unlikely to me.

> Renewables are obviously not cheaper than fossil fuels in any general sense because we are still building coal and gas plants all over the world for purposes well beyond having flexible energy sources

This is in fact not true; having flexible energy sources has been the primary reason for building gas plants for decades (gas is usually more expensive and always less portable than coal), and coal plant operation and construction is being canceled all over the place. Outside PRC, not even enough coal plants are being built to replace those that are being decommissioned, and the coal industry is suffering extreme economic hardship as renewable energy replaces it through a combination of better prices and political programs.

https://chinadialogue.net/en/energy/2020-a-dismal-year-for-c... 45 GW of coal power construction cancelled in Bangladesh, Indonesia, the Philippines, and Vietnam because investors pulled out, leaving only 25 GW planned.

https://www.climatechangenews.com/2021/02/25/bangladesh-scra... details on the 7.5 GW of coal cancelations in Bangladesh.

https://balkangreenenergynews.com/europe-is-halfway-into-clo... European coal output has been cut 60% since 02000, and projections are that they'll shut down 50% of the remaining 162 plants by 02030 (though 36 new plants are being built).

https://www.eiu.com/industry/article/589070442/europe-coal-u... In 02018 European coal power output was 619 TWh/year (71 GW), down 24% from the year before, which probably means European coal generation capacity was about 120 GW; "renewables have been squeezing out coal" and now account for twice as much electrical output (not capacity) as coal.

https://www.nytimes.com/2017/01/18/world/asia/china-coal-pow... China cancels construction on 103 coal power plants totaling 120 GW (an entire Europe's worth) four years ago, including plants where construction had already begun.

https://ieefa.org/peabody-energy-flirts-with-bankruptcy-agai... Peabody, the world's biggest coal company, went bankrupt 3½ years ago and is at risk of going bankrupt again; "Coal bankruptcies in the United States have become increasingly common. Cheap gas and renewable power have steadily replaced coal in the U.S."

https://pv-magazine-usa.com/2020/05/28/record-low-solar-ppas... the 1GW San Juan Generating Station in New Mexico is unprofitable because its US$44.90/MWh operating cost is almost twice the average energy price at the Palo Verde Trading Hub (US$26.58/MWh) and three times the price on new solar PPAs (US$15/MWh); not mentioned in the article, but this is also why the 2.2 GW coal Navajo Generating Station, the largest in the US, was just demolished.

Now, there are some places where coal power generating capacity is increasing. PRC built 38.4 GW of new coal power capacity last year. But it also built 48.2 GW of new solar capacity and 71.7 GW of new wind capacity.

Outside PRC, worldwide coal generating capacity fell by a net of 17.2 GW in 02020, while PRC's net coal power capacity increased by only 29.8 GW (so 8.6 GW were decommissioned): https://www.reuters.com/article/us-china-coal-idUSKBN2A308U

This despite the fact that 50% of PRC's coal power generation is unprofitable and there is an epidemic of bankruptcies: http://www.xinhuanet.com/power/2019-08/22/c_1210252090.htm Factors cited include "low electricity prices" and "new energy competition" ("新能源竞"), meaning wind and solar.

(For scale, worldwide bitcoin mining is estimated at 12.5 GW. China used 836 GW of electricity in 02019 and about three times that amount of energy.)

And, as explained in the articles I linked in my previous comment, solar is not cheaper everywhere yet. Polar countries like Germany, the UK, and the Netherlands have very poor capacity factors (around 10% for fixed PV). But the vast majority of the world lives in places with much more sun than that, so for them solar is cheaper. Bitcoin mining, as I explained, doesn't care where it happens.

> You've swapped now to "The UK will just not mine locally because they are never going to switch off coal" when the original argument was "BTC adoption will speed world transition away from coal".

I have not swapped, and I do not endorse your attempted restatement of my thesis. Allow me to clarify.

Today, PV in the UK is not cost-competitive with coal because even though PV modules cost 10% what they did ten years ago, they are still too expensive to be cost-effective in such a marginal region. Also, possibly the UK needs to build more energy storage—not necessary for bitcoin mining, but necessary for some other uses of grid power. What drives the price of PV modules is the learning curve: a 20% price reduction for every doubling of shipped volume. Another couple of doublings in volume, whether driven by bitcoin or (as seems overwhelmingly more likely) just general industry, and we'll get the price low enough to beat coal in the UK too. But not low enough that the UK can mine bitcoin profitably.

https://en.wikipedia.org/wiki/Swanson's_law

This learning curve for PV modules is an empirical phenomenon with vast amounts of data to attest to it, and it's so fast because PV is such a new field that's still in a rapid exponential growth phase. The absence of such a rapid improvement in costs for fossil-fuel technology, and indeed the gradual increase of its cost due to resource exhaustion, is an even better known phenomenon, one which has been central to geopolitics for half a century.

So, I do think bitcoin mining will speed the world transition away from coal, by subsidizing the development of solar panels and solar-panel factories, which drives down the price of energy, although the total effect is small. Although even in China bitcoin mining is not currently a major percentage of total electricity consumption, much less total energy use, it is a percentage with characteristics that have already driven it to be peculiarly dominated by renewable energy, and those characteristics are intensifying. I do not expect bitcoin mining to become such a large industry that its effects on the renewable transition, though positive, will be large. But bitcoin mining definitely moves the world, even if in a small way, in the direction of a world where net CO₂ emissions are not merely small but actually negative.

It is understandable that, since you were unaware of the most basic facts of the situation, you were unable to apprehend the causal relationships in play, and misinterpreted perfectly straightforward points like the ones I was making. Hopefully this quick primer will save you from making such embarrassing errors in the future!

However, I am done explaining things to you.

Fiat currency not controlled by major economic powers has been know to do that (and there are a few cases for major powers, too, in conditions like just after losing major wars with other such powers.)

Conversely, if you aren’t a major economic power, a fiat currency that is controlled by one is at the mercy of other countries. (And, even if you are a major power, your currency has some exposure to your relationships with othe countrieds, though “at the mercy of” may be too strong.)

Not all fiat is “the USD from the perspective of the US”.