With Bitcoin you do not get government bailouts like what happened with the beyond reckless banks in 2008.
Bitcoin is not an immutable law of nature. If the coin minting cap is reached, all that needs to happen is for miners to start running a fork with a higher cap. Tada, more coins conjured out of the ether, just like all the previous ones. If you want enforced scarcity, you need to be tied to something physically scarce.
First thing that comes to mind off the top of my head as a US-Govt option here would be something like: bail out US people/companies of bitcoin holdings in USD in conjunction with banning bitcoin in the US going forward. So that would be quite the string of events at that point for non-US bitcoin holders: first a crash that caused all these US bitcoin holders to go screaming to the government for help. Then the overnight removal of a huge chunk of the bitcoin market, coupled with either a firesale to comply with the ban or US gov seizure of a bunch of the coins, which will push the price lower for anyone who hasn't sold yet since their buyer pool is now much lower.
It is not beyond imagination that the most popular Bitcoin blockchain (and thus, the label of being the "real" Bitcoin) could change at some point in the future.
"Bitcoin" is not immune from the implications of political fuckery.
I don't know what the specific mechanism would be, but I would bet that it relates to the billions of dollars backing the current ecosystem, and the interests of the people behind them. If the right event or crisis comes along, then people could be compelled to switch over to something else.
I'm sure there's someone out there still mining blocks on that chain with the exploit from 2010, but that's not where the mining power is. If the right series of events occurs, the miners will switch.
Governments around the world are 100% attempting different plans to destabilize or destroy Bitcoin because it harms their interests and ability to print money from thin air. But at the end of the day it's a distributed ledger, so even if they do find a way to manipulate or damage or takeover the network the Bitcoin users can just fork it from before they did their damage and continue from there. That is the ultimate power of a decentralized blockchain, nobody has ultimate power and everyone votes with their resources.
It's that everything you do on the blockchain is there forever, so if a government needs you in jail for using it, they can show you were involved in a financial crime and the blockchain proves it... And if you are unwilling to give up your public wallet they can keep you in jail indefinitely until you do.
Bitcoin is pseudonymous, not anonymous. Every activity on the network is encoded into a perpetual auditable dataset, by design.
The government of Ethereum is not the US government.
