Nick Szabo  🔑

The cost of reorging the whole chain is lower than total value of the network. For a large enough payment you cannot rely on waiting for enough confirmations to accumulate PoW in order to make it economically irrational to revert. Security is not just PoW.

That means Bitcoin doesn't secure such a large transaction. Something else may or may not secure it, but Bitcoin does not. What did you think it meant?

I see. Do you have a post explaining this in depth? I’d mainly want to understand if you consider coin issuance one of those large paymets, with many recipients, or you think coinbases are different from single tx payment outputs.

Bitcoin protocol is enforced by people that use and validate the bitcoins they receive. When you talk about a long period re-org, that's a man-made attack. I personally would refuse to follow that chain and pay fees only to the miners that work on the legacy chain.

In other words, you would fork. Others wouldn't. The result would be a disaster encouraged by this soothing nonsense. To claim that this is a great way to secure large transactions, so don't worry rely on that 100,000 BTC you just received afte just a few confirms, is ludicrous.

1. Yes this would mean a fork. But that would mean that economic actors (exchanges, companies, users) would have to decide which chain is the correct one and people would sell/buy the coins that are relevant for them as Bitcoin.

It's a disaster, not a security protocol. And txs aren't just a theory any more, they are starting to happen. Are you really going to put Bitcoin's reliability on the line for the sake of soothing some ultra-whale? "Go ahead screw BTC with a big tx, we'll bail you out."

ok I think I understand what you are saying: if people have to take action to invalidate a re-org (hard-fork), than the security proposition of Bitcoin is invalidated, which stated that the proof-of-work is enough to know the truth. Is this correct?