I don't think a successful 51% attack would kill Bitcoin at this point nor do I think anyone capable would be willing to attempt it.  It would take a great deal of equipment and money to pull off such a thing.  I do like the idea of governments with massive amounts of hashrate closely monitoring chains for any sort of forking while they wait for a massive transaction to receive confirmations.  Makes me think of the new Loki show and divergent timelines being managed by the timekeepers...

They can succeed but in a short period only. The Bitcoin community will detect their attacks and react quickly to stop governmental attacks.

Geolocations don't mean they are identities of ownership. In same geolocations, you can find different mining companies and their hash rates belong to different owners.

Full nodes can detect IP address as I know. I read some documents that in order to have better privacy for your bitcoin transactions, you should set up your Bitcoin full nodes and broadcast your transactions from your full nodes.

I agree with OgNasty in that I think bitcoin would probably survive a short and specific 51% attack. By that I mean a 51% attack which double spends a handful of specific transactions, as opposed to a prolonged and sustained attack just mining empty blocks to censor the entire network, or something similar.

There are too many people involved in bitcoin who either don't care or don't understand the importance of a 51% attack, blocks being orphaned, or transactions being reversed or censored. Look at some of the "top" altcoins. Ethereum - not a classic 51% attack but effectively the same result (majority of hash rate reversed some transactions), creating Ethereum Classic in the process, which itself has been 51% attacked several times. XRP, USDT, BNB - completely centralized, can have transactions reversed or censored at any time by their owners. BCash - successfully 51% attacked. And yet all these coins continue to have volumes of billions of dollars and attract new users.

Provided that the 51% attack was short lived, and bitcoin continued to function normally afterwards, then there might be a hit to the price, but I don't think it would be the end of bitcoin.

Suffice it to understand what you're attacking. The revolution set sail; you can't stop it, just like you can't kill an idea.

Seriously, think it. Do you really believe that after this revolutionary creation, people will simply forget it? That this innovative technology will be gone just because the government says so? That we'll let slip the PoW mechanism combined with a chain of blocks containing immutably information?

By attacking Bitcoin, you actually attack your own wealth. Masochism...

Which ones do you have in mind?

Isn't Ethereum fine? I've read that ETC was 51%-ly attacked, but that was long after ETH was hard forked. Ethereum Classic was made due to a hack of a third party project.

But, Bitcoin, after all, is an idea. The fact that someone may catch up and gain the majority of the votes doesn't mean that he ruins the system. It's an idea which transforms human's greed to common good, which discourages you from attacking it, but rather helping it so you can earn the most.

There's harmony in this consensus and the only ones who can destroy it are the ones who make this beautiful melody.

You may need no Bitcoins, but you need wealth. You can't plan to spend billions of dollars worth of ASICs and electricity and retain their work until further notice (?), without damaging your own wealth. Besides, what could they do on a PoS crypto? Buy half of its units? They can't attack everything and that makes the 51% attack of Bitcoin meaningless.

There are greater achievements in terms of technology than Bitcoin. Sure thing, it was created in 2009 which has its downsides. Phenomenonically, it'll always be the #1, but in terms of privacy (e.g.), it can't be compared with Monero (e.g. again).

In my opinion, without Bitcoin the whole industry would become chaotic.

People sometimes overestimate the cost for this, they take new gear at resale value, they think in power at residential tariffs and so on..

To launch a 51% you would need roughly 1 million s19pro, that would be 7-8 billion $.
But if I would do that I wouldn't go for that gear, I would grab s9s that sell for around 250$, and instead of paying 8k for 110th/s I would get away with 1500$.  So rather than 8 billion, you're down to 1 and a half. And there is a ton of cheap useless for ROI gear sitting in China with no buyer, you're not going to make a profit with it but you'll definitely get a far better price per TH than with the newest generation. Besides, you don't need it to run for a year, one week and it's enough.

The other thing is energy, the first part is quite amusing, every time when it's about bitcoin, everyone says bitcoin is using only 0.01% of the energy in the world, now when you need to attack it, god that's a lot of energy and nobody can get it!!!! Back to the math, miners can't spend more on energy than the reward, so to match them you will need to spend a max of 45 million a day, but you're the government so no taxes, it will get way cheaper. If we go by 10cents/kwh it will still only cost 20 millions to power 6 million s9 a day.

Now, let's assume that indeed Bitcoin is threatening the US dollar, and the US who spends 13 billion on a Ford-class carrier won't be able to pull that off?
But nobody is interested to do so, why do it?  It means people in your own country losing wealth, it means stopping an activity and dealing with people that once had a job and now are on the unemployment payroll, why? Because it will replace the dollar and it will do that and that? Common...


Once the value is gone so is the hype. The idea for which Bitcoin was created get's more tainted every day, look at the ecosystem now, it's all about centralized exchanges and wallets, prices and trading, and holding till you make x in profit, once that is gone you will never be able to find the same userbase again, the ones that are reticent to the idea will never embrace it after such a failure, and from their point of view is quite understandable.

I'm just saying that there's no reason to do it. Spend more than a billion dollars to attack something that works under a general agreement. You may indeed achieve to destroy the Bitcoin network, but you won't get rid of your worries. Proof of stake cryptocurrencies will then arise. What will they then do? Buy half of the units? There will be other permissionless and borderless cryptocurrencies they'll be afraid of; beating Bitcoin doesn't beat this liberated attitude.

Yes, this is how the world works, I know. The majority of the people don't want to be responsible for their wealth. Hence, centralization occurs.