[lrvick]

If 51% of US politicians all decided the value of the US dollar should become 0, then it would be so... and yet it is still a representative democracy which is a decentralized form of governance.

This is unlikely to happen, because it would be to no ones advantage. Even if they did most of the public would likely just ignore the decision.

https://www.crypto51.app/ covers this question in regards to cryptoassets.

It will cost something like $1m/hour to attack Bitcoin, but to even do that you would already need to actually convince 51% of miners to light their profits on fire for no reason.

Even under a very expensive and sustained attack the users of Bitcoin that wish it to have value would simply distribute a blocklist for the compromised nodes and carry on with the 49% that wish for the network to continue as well.

[anonymouskimmer]

> "If 51% of US politicians all decided the value of the US dollar should become 0, then it would be so..."

You don't understand how things work in the US. There are multiple checks and balances. And if push truly came to shove enough of those politicians would be assassinated to make it 49% (dear FBI: this is a hypothetical as to what a few members of the public would do, not what I, personally, would do). Good luck assassinating a Sybiled validation node.

> "This is unlikely to happen, because it would be to no ones advantage."

No one who has bought in to the protocol. But of advantage to an entity that wants a particular protocol to fail.

> "Even under a very expensive and sustained attack the users of Bitcoin that wish it to have value would simply distribute a blocklist for the compromised nodes and carry on with the 49% that wish for the network to continue as well."

Yes, you'd get a forced split. Can you guarantee that the 51% attacker couldn't gradually hop back on and attack again?

[lrvick]

> Good luck assassinating a Sybiled validation node.

No need. We distribute it on an IP blocklist and carry on, just like we handle bad actors on other decentralized systems like email.

Remember that chain splits have happened before and the minority chain and those that agree with its rules and history continue on. Eth Classic is still a thing.

Modern Eth was literally an -intentional- 51% attack to erase a hack. The majority agreed to erase that and on the main ETH network, it became so.

> No one who has bought in to the protocol. But of advantage to an entity that wants a particular protocol to fail.

Once again, we can easily detect and block nodes that are repeatedly trying to lie. It would be annoying, but so is dealing with spam. This is inevitable but manageable and without violence I may add.

> Yes, you'd get a forced split. Can you guarantee that the 51% attacker couldn't gradually hop back on and attack again?

The community could ban all of their nodes and assign higher trust to nodes that did not participate. Any fullnodes that agree they are on a fraudulent chain could agree to go back to the minority chain.

If it happened often we would get better at doing this quickly.

In short, you can temporarily disrupt the Bitcoin network with enough money, but you will never be able to stop those that wish to continue maintaining an honest history.

[anonymouskimmer]

> "In short, you can temporarily disrupt the Bitcoin network with enough money, but you will never be able to stop those that wish to continue maintaining an honest history. "

If your goal is to make regular people want to avoid using it all you need are sufficient temporary disruptions.

[lrvick]

The internet has had many many temporary disruptions over the years due to botnets, etc. The Slammer worm even fully made it inoperable globally. The will to continue communicating at a distance lived on though, and so did the internet.

There are plenty of people like me that actually use and rely on Bitcoin as a tool, so it will live on too.