1) they will just physically lock you up if you refuse to hand it over.
Today, in isolation, if you did that right now, after you've withdrawn the money from your bank account, yes they would lock you up.
My point is in the context of a government that tries to take the piss with everyone by trying to tax us all unreasonably. If millions of us did that (And it would be legal, I'm no expert in common law or taxation law), there is definately a law that allows citizens to declare that the goverment is being unjust and that payment of taxes are being witheld. BUT you are expected to eventually pay such taxes.
It comes back to what I call the government's cost to persecute an individual.
- It costs a lot of money to arrest someone, try them and chuck them in prison - which is the only option if the money is hidden.
- It costs some time and money to seize someone's bank account.
- It will cost them peanuts to seize CBDCs potentially without much oversight or recourse.
I'd live with scenario 1.
Plus look at what the FBI are trying to do with tornado cash right now. They can block you from spending that money by requiring merchants refuse payments from your wallets. Those merchants will accept the request because to refuse would mean no longer being able to do business in the country whose government they are dealing with.
So yeah they can't "confiscate" your crypto, but they can sure as hell stop you from being able to do anything useful with it, and they can lock you up if they choose to do so.
The situation around Tornado Cash concerns criminality in the form of state sponsered hack attacks from hostile states such as North Korea who have used the service to frustrate the authorities in their quest to hunt down the money.
That is a wildly different scenario than people not paying their taxes. They see the former as a national security issue.
The FBI has blacklisted wallets that used by the actual Tornado Cash project NOT the wallets of people who have used Tornado Cash.
They aren't threatening to blacklist the wallets of people who use Tornado Cash in such a way, that other people aren't to do business with them.
It's simple. If you are a US citizen and you use Tornado Cash, you may be prosecuted. There has been NO threat to blacklist the wallets of those that don't comply, HOWEVER, as night follows day, you can bet that no centralised exchange that has operations in the US, will do business with anyone who uses Tornado cash from yesterday onwards.
People have no practical way of checking which governments around the world have blacklisted what wallets, however, if my own government says "You all need to stop using Tornado Cash or else." - then of course, it's easy for me to follow that dictate.
How would the US government blacklist millions of wallets of people that it's pissed off with and seriously expect everyone around the world to comply? That's not going to happen. The US govt would never try and pull that kind of a stunt because they know that citizens around the world would see them as the problem, not Korean hackers.
On the other end of it, if Tornado Cash has any sense, they'll be blocking US IP addresses from their websites.
By the by, the FBI wouldn't have bothered going after Tornado Cash if it was properly decentralised. Many say that they aren't.