Untraceable if you use a mixer. Why not blacklist coins that have been mixed? It's not hard to figure out whether a coin has been tumbled through e.g. bitcoinfog.
I think most of the resistance to this idea comes from people who've used Silk Road clones, most of which force you to mix your coins. But as bitcoin becomes more valuable and ransomware more prevalent, the argument that silk road is ethical and should therefore be able to function becomes less and less persuasive.
Blacklisting the coins would be easy: Exchanges simply close your account if you receive a large number of BTC that have been tumbled. It's easy to identify the coins and to easy to close the accounts while refunding the coins.
“Untraceable” is a strong promise and I'd be surprised if traffic analysis couldn't de-anonymize effectively with the investigatory resources which a nation-state can muster.
The other key thing is that Bitcoin fails open: if anyone anywhere ever makes a mistake or is subverted the blockchain is a public record of every transaction which is hard to deny and can never be purged. I'm not sure anyone has the operational competency to make assurances in that environment.
Blacklisting the coins would be easy: Exchanges simply close your account if you receive a large number of BTC that have been tumbled. It's easy to identify the coins and to easy to close the accounts while refunding the coins.
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Seems like the future will be full of black-market banks and money laundering (as opposed to how its always been ;-) #PanamaPapers)
Is this the most difficultt financial problem: We don't want government watching every single move we make, yet we dont want criminals to be able to easily hide all their nefarious actions...
Where is the correct balance?
We have those who are supposedly the beacons of the tech future now being revealed as just as bad as others...
Faith in humanity is being assaulted a fair bit more than it had been in the last few decades...
I think most of the resistance to this idea comes from people who've used Silk Road clones, most of which force you to mix your coins. But as bitcoin becomes more valuable and ransomware more prevalent, the argument that silk road is ethical and should therefore be able to function becomes less and less persuasive.
Blacklisting the coins would be easy: Exchanges simply close your account if you receive a large number of BTC that have been tumbled. It's easy to identify the coins and to easy to close the accounts while refunding the coins.