snip
Bitcoin is open source; you can't control the software. It's an impossible task. Suppose the United States makes paperweights called Bitcoin, what's the difference? Would they control Bitcoin because of that? It's absurd. From the moment you fork the Bitcoin code, it ceases to be the original, and the US will never have the power to confiscate all the unguarded private keys.
You don't seem to understand how Bitcoin works. Most users wouldn't notice any difference at all. Your keys would still work, as would all of the tools you use. The blocks would be copied. The only thing that matters is the set of servers that the tools point at, and when ever major tool like the brokers, the wallets, and ETFs and the major holders all point at the US government-approve network, then most people won't even know anything changed, and they wouldn't care.
Meanwhile, the original network would be declared illegal, and anybody who offered a tool that pointed at and still called their product, "Bitcoin" would be prosecuted in the same way that they would if somebody created their own fork and called it "Bitcoin".
As soon as laws are passed that harm these companies, they'll flee the country, I assure you.
These companies would be faced with losing all of their money or simply complying with the new law. It's obvious what choice they would make.
I myself care about the value of my life savings that's into Bitcoin, but I don't think everybody, except 0.00002% of them, would leave Bitcoin if your scenario becomes real. I don't think Bitcoin's decentralization has no value today.
Of course they wouldn't leave "Bitcoin". They would leave the now-illegal thing that can no longer be called "Bitcoin".
They would choose the network where their coins were the most valuable.
One network would have the major holders, the US president, Elon Musk, Michael Saylor, CoinBase, Binance, Robinhood, Blackrock, all of the ETFs, and basically the entire US financial system there to help keep it trading and valuable.
The old fork would have... a bunch of pissed off Bitcoin hardcores who only cared about the religion and not the money.
In other words, 99% of the money would be on the US government fork. Duh.
As far as I know, anybody who self-custodies Bitcoin can still send Sats to anybody regardless of his/her race, nationality, religion, political beliefs, and whatnot until today, and could rest assured that his/her Bitcoin kept in a self-custodial storage remains safe from any government agency that wish to seize it.
Um, self-custody does not protect you from a government anymore than hiding a stolen car in your garage or gold coins in your basement does.
Also, believe it or not, ~99% of Bitcoin is probably
not used for criminality and tax evasion, it's simply an investment for most people.
Besides, people who want to do criminal stuff and keep their money from the government use
Monero these days. Bitcoin is an open ledger and traceable--sorta lousy for doing crime.
How would the Bitcoin architecture be changed?
In another thread, we discussed how the Bitcoin network could be scaled to handle everyday payments, which would make it much more useful, and probably much more valuable--but it would require dropping PoW and making the architecture much more centralized.
Anyhow, that wasn't the point of the OP. The point was that it's not "impossible" that Bitcoin be taken over by the US government. In fact, it's already been heavily regulated, and taking over the network itself would be trivial since it's the US government that enforces the trademark, "Bitcoin".
How significant is Bitcoin that the US government would be ready to go to war with other countries just so they can denounce Bitcoin and accept the new fork?
"Denounce"? They would be
improving Bitcoin, at least in their own opinion.
Simply increasing the hard cap to 50 million will make investors lose trust in Bitcoin,
So they wouldn't do that.
I'll give you a hypothesis where if the US tries to bully other countries to accept its fork, China and Russia (even though I don't rate them much in this kind of scenario) would oppose it, and would back many other countries.
So what. Almost all of the market cap from Bitcoin comes from the US financial system. And they don't need to own it all in order to effectively blackmail everybody else into accepting their fork.
Are you saying the control of Bitcoin is worth going to war over? For an asset that may lose its value while you are fighting for it?
China and Russia didn't even go to war with the US over Venezuela and Iran.
Why would China or Russia care what the US did with Bitcoin? Especially if their own holdings were perfectly safe and still tradable? If the Russian government hated it, they could just sell their Bitcoin and buy some other crypto, or gold, or whatever.
I know y'all love The Bitcoin Religion a lot, but nobody is going to go to war over it

.
Be careful with what you write on this forum. You might trigger all the Bitcoin maximalists and fanatics.

Gee I hadn't noticed

.
Maybe Bitcoin has become "too big to fail". Any form of direct government intervention would crash the BTC price and many investors and corporations, that hold BTC would lose a lot of money. No government in the world wants to cause damage to wealthy people, because, you know, wealthy people are the ones, who donate money to the politicians(not just donations, but bribes as well). The US government is pretty much OK with the current state of Bitcoin, so there won't be any government backed forked version of Bitcoin. There are hidden forms of manipulation, that can achieve the goal without having to openly attack and impose direct control over a technology or an industry.
That's a very good argument for why the US government would not
want to do this. But that's not the point of the OP. The point was that the US absolutely
could do this if they wanted to.
And that means that Bitcoin is absolutely
not impervious to government control like the hardcores keep saying it is.
The US government hasn't taken over the Bitcoin network because they don't feel like it, not because it's impossible.
I would call that an illogical theory, because a fork is a fork and it cannot replace the main coin or its blockchain,
A Bitcoin fork using the same chain data could create a fully compatible product that would preserve everybody's coins. There have already been many projects that do this. They aren't called "Bitcoin" like the US government's would be called, but they work exactly like Bitcoin, including using the same blockchain.
Besides, why would companies and individuals such as Michael Saylor be interested in something like that when they know this is only going to cost them since they are making so much money through Bitcoin right now?
The OP is not asking why they would do it, only pointing out that's its entirely possible and not even that hard for them to do. So please stop saying, "Bitcoin cannot be taken over by governments" when it absolutely can be.
If it was that easy for the US government to erase Bitcoin by creating a version of it and imposing it on people then they would have done this a long time ago,
No, they wouldn't have. Bitcoin has been defacto legal for at least 10 years now. There are gigantic public companies who own Bitcoin, as does the president of the United States. The reason the US government hasn't taken over the Bitcoin network is because they haven't found a reason to do so. But they easily could.
This is exactly how the trademark of Bitcoin works today .
The reason why somebody can't come out with a new memecoin and call it "Bitcoin" and use the BTC symbol for it is because of trademark protection, and that protection comes from... the US government.
Another factual error, I am tried of counting your utopian theories.

Governments enforce trademark laws, they do not create trademark rights out of a vacuum.
Insofar as "nobody" owns the trademark "Bitcoin", then it's a public thing, and therefore
governments will define it. Today, if you came out with a fork and called it "Bitcoin" and it didn't use the network they think it should use (e.g. the one everybody uses right now for instance), then the US government would prosecute. But that definition is completely up to the US government since there is no original owner. If Bitcoin is not a trademark, then the problem is still there: the US Congress needs to define "what is Bitcoin" in order to defend against fraud. Today that definition is implicit, but it could be made explicit, and it could be anything they choose it to be, and they could change it over time as well.