If someone had quantum computing power, they wouldn’t attack Bitcoin.
They’d quietly drain banks, move into Bitcoin, and disappear.
Bitcoin isn’t the target… it’s the exit.
Bitcoin is pseudonymous, transparent, monitored & upgradeable.
Discussion
It's regularly said that we're still early. To the degree that that's true, doesn't that imply that an attacker likely wouldn't see Bitcoin as an off-ramp? And even if the first attacker does, what if the 2nd, 3rd, ... Nth attacker doesn't?
Quietly and quantum isn’t a match.
Bad take.
Banks can upgrade in minutes. It's very hard to take money out. There are several ways to reverse the transaction. Plus breaking encryption with quantum is not enough to hack banks, you still need user credentials.
This will almost certainly not happen.
Look up daily withdrawal limits
Bankside, cardside and atm side.
The putative quantum attacker would be unwise to steal things the market value of which would tumble instantly after the theft.
Exactly
Disagree with the reasoning of this thread. Because you can short Bitcoin massively, theoretically much larger than the entire market volume of Bitcoin. For example, the CME Bitcoin spot is a synthetic derivative of exchange prices and doesn’t have to resolve on actual Bitcoin trades. And if you buy puts and sell calls with “stupid” by current market logic strike prices, you could easily entice large numbers of traders into the contracts.
Secondly, aggressively shorting Bitcoin timed before a Shor’s attack could likely earn you tens of billions of dollars, legally. Nobody is going to choose to earn fickle, likely uncashable fake money from hacking banks when you can become a multibillionaire overnight via shorting Bitcoin and keep all the profits.
Thirdly, the people with access first to the number of qubits necessary to do a Shor’s attack on Bitcoin are going to be extremely well capitalized people. Access to quantum computers is currently extremely limited and only available to select institutions. The type of people with access are not going to go on a crimespree. They are incentivized towards protecting the banking system and destroying Bitcoin, not the inverse.
Finally it’s very easy to hack banks already. I’ve never seen a major retail bank I couldn’t break into. It’s stupidly easy to hack banks. The hard part of breaking into banks is not compromising the computers, it is getting the money out.
A viable quantum Shor’s attack would be first used on Bitcoin and nothing else.
Personally, I think Bitcoin will be patched to guard against quantum attacks and a new wallet format will be added like happened for Segwet, far before we get to the point that quantum is a threat. And everyone serious will just add one of these new Quantum wallets to their storage wallets for multisig. So I am not very worried about a quantum attack against Bitcoin, at least not currently. If there were quantum computers close to the likely the number of qubits necessary and no progress on the Bitcoin front I might change my mind. But it is not a concern of mine. But I think the logic people are using to say quantum is not a concern, which this thread is a microcosm of, is very fallacious.