[georgyo]

Cash is completely fungible because there is no clear trace of money from one person to the next.

If someone steals 100k of cash, there is a very low probability that the serial number of those bills were recorded somewhere. And even if they were, you couldn't easily trace the money though complex systems.

Bitcoin on the other hand is a complete and open ledger. When these large heists that constantly happen, it is trivial to identify the transactions that happen afterwards.

Cash is actually anonymous and Bitcoin is only pseudo-anonymous.

[iszomer]

Which iirc was the basis for "cleanly mined" btc with little to no transaction history on-chain and tumbler/mixer services that attempted to obfuscate it.

[hashimotonomora]

The fact that it’s difficult or expensive to track does not mean it cannot be. Technically it’s possible to force every cash handling business to scan (just like you scan an UPC) each bill.

[bena]

"This note is legal tender for all debts, public and private."

If I buy you lunch today, you can pay me back next week. We're not "cash handling business[es]", so we wouldn't have to scan.

Second, I don't think it's technically possible. For companies that do business across state lines, sure, but within a state's border, interstate commerce laws don't apply. Each state would have to enact a similar law. And best of luck with that.