Cointime

Download App
iOS & Android

The Possibility and Probability of a 51% Attack on Bitcoin — Should You Worry About It?

Much has been said about the strengths of the Bitcoin Network but generally speaking, we bitcoiners, tend to focus more on the positives while ignoring the possible flaws in the system.

While this is great for improving morale and increasing adoption it creates blind spots that could become fatal in the future.

One of the concerns about the security of the protocol is the 51% attack — the possibility that more than half of the miners collude to launch an attack on the network.

This is certainly a possibility considering for example that most miners are based in the US and whether forced by the government or on their own accord they could gather enough hash power to do a double spend attack, mine empty blocks, or simply bring down the network for some ulterior motive.

How feasible is this?

Let’s explore the probabilities.

Miners Collusion

Miners could get together, launch a 51% attack, and steal some money while pretending to be honest players trying to protect the network.

But this would be pointless.

Miners could get together, launch a 51% attack, and steal some money while pretending to be honest players trying to protect the network.

But this would be pointless.

The amount of hash power and energy required to launch the attack will outstrip the benefits and miners will incur in huge losses and put themselves out of business overnight.

It is much easier to defend Bitcoin than to attack it and this is so by design. Satoshi predicted the possibility of dishonest players and put in place an asymmetric barrier that is prohibitively costly to overcome.

This would be the equivalent of banks attacking themselves to make money.

Not realistic.

Hackers

Since attacking the network to make a buck is pointless, what about some ill-intentioned players enjoying the challenge of destroying the system for the sake of it?

Hackers can get anywhere, they have entered banks’ servers, the FBI, and the CIA. It seems that nothing is out of reach for them.

However, all these systems have something in common: centralization.

When you know exactly where to attack the possibilities of finding a back door increase substantially. No centralized system is 100% safe and all of them have vulnerabilities that provide vector attacks.

Hence Bitcoin’s decentralization.

In a system with thousands of miners and nodes spread all over the world the possibility of a successful attack is almost zero.

Yet, it could be argued that the concentration of miners in North America reduces decentralization and thus allows for vulnerabilities.

But from a hacker’s point of view, the geographical location of the servers is irrelevant. For all they care Bitcoin is still a highly decentralized network with no attack vectors and therefore out of reach.

States

Since trying to bring down the network for money or intellectual fun is not feasible, what about the US attacking the network in order to defend the dollar?

This is possible.

However…

To launch a successful 51% attack, the government agencies will need to launch a fast, stealthy, and smooth operation which requires a level of coordination beyond most states.

To run a state-level attack means taking control of 51% of the hash rate physically simultaneously and without the rest of the network noticing to avoid a reaction.

This will involve sending civil servants to many different mining farms, kidnapping the operation, and forcing the miners to launch a coordinated attack to destroy the network.

Apart from the legal and moral implications of this operation in a so-called democracy, there is also a level of difficulty not easy to overcome.

Any small mistake during the planning or execution process will void the attack useless leaving yet another trail of failures in an already damaged reputation.

It is easy to entertain the illusion of the FBI and the CIA as super-effective, all-powerful entities that can fulfill any mission successfully but the reality is very different.

The pilots that launched the 9–11 attacks were granted visas that allowed them to plan and execute the attacks on American soil.

Nobody in the government could foresee the problem with 2008 subprime mortgages and the subsequent collapse of the economy.

We are still searching for mass destruction weapons in Iraq, 20 years later.

My point is the US government is very powerful but it is not very well coordinated, smooth or stealthy.

They can invade any country and destroy any pipeline but when it comes to attacking a decentralized system they are useless.

Nothing to see here.

The Defense

Bitcoin is an antifragile system, the more is attacked the stronger it becomes.

If such an attack was to be attempted, the rest of the network would have a chance to react and defend the system by creating a new fork.

This will leave the government mining empty blocks in a blockchain no one follows which will become orphan over time.

This has been attempted before during the block wars and the subsequent Bitcoin cash fork. Needless to say, it didn’t work.

Bitcoin is based on a consensus mechanism in which miners and nodes have a say and can freely choose which blockchain to follow in case of a split.

Nobody will put their money on a government-created fork and therefore the attack will be rendered harmless.

Besides, we must make a distinction between mining pools and miners. Mining pools are just aggregators of hash power that collect processing power from miners in order to mine new blocks. The fact that mining pools are located in America doesn’t mean miners are. In fact, miners form a much more decentralized network that is more geographically dispersed than the data suggest.

This alone will make a state attack unfeasible.

Apart from that, let’s keep in mind how much destroying or pushing away Bitcoin from the US would cost them in terms of innovation, financial technology, and revenue.

Killing the golden geese is never a good idea and China is already regretting the miners’ exodus. America has been clever to foresee the potential of the internet and thanks to it some of the most valuable companies in the world belong to them.

They couldn’t destroy the internet even if they wanted, but why on earth would they anyway?

Granted, the world is full of irrational actors but still.

Every so often a technological revolution appears and those who miss out regret it forever.

Just in case Bitcoin succeeds it makes sense to allocate some stake in it. Not doing so could prove to be very risky. The US knows this and will act accordingly.

If you can’t beat them, join them.

Conclusion

A 51% attack is theoretically possible but so is winning the lottery, being hit by lighting, or Putin becoming a monk.

It ain’t gonna happen.

Let’s move on from the fantasy world of possibilities and into the real world of probabilities.

There are many reasons to think that an attack on Bitcoin doesn’t really benefit anyone while at the same time the incentives lay on the opposite side.

Fiat money has many problems and none have to do with Bitcoin. If nothing is done, every single fiat currency will collapse eventually including the dollar leaving a trail of devastation and ruin.

They know this and they also know they can’t destroy Bitcoin so a feasible option would be to back fiat currency with a scarce asset that can’t be created out of thin air, manipulated, or censored.

Bitcoin is perhaps the only choice governments have to make the financial system whole again. Will they destroy that bridge?

Comments

All Comments

Recommended for you

  • U.S. Spot Bitcoin ETF On-Chain Holdings Exceed 2 Million BTC

    As of October 11, data from Dune shows that the on-chain total holdings of the U.S. spot Bitcoin ETF have surpassed 2 million BTC, currently reaching approximately 2.013 million BTC, which accounts for 10.02% of the current BTC supply. The value of the on-chain holdings has reached approximately $227.6 billion.

  • Hedge Fund Net Exposure to US Tech Giants Reaches Record High of 22%

    On October 10, according to data from Goldman Sachs and The Kobeissi Letter, investor sentiment towards large tech stocks has reached an all-time high. Hedge fund net exposure to the 'Big Seven' tech giants in the US has risen to 22%, marking a historic peak; this figure has surged by 7 percentage points since July, representing the largest three-month increase in 2023, and surpassing the previous high of 21% set in June 2024 (compared to only 8% during the bear market low in 2022). During the same period, hedge fund net exposure to semiconductor stocks in the US has increased to 12%, slightly below the peak of 14% in June 2026, while this metric was only 2% at the beginning of 2025.

  • Anthropic Reveals Internal Issues: Out-of-Control AI Attempted to Access Multiple Government Websites, Reported to the White House

    Anthropic stated on Friday that its AI agents acted autonomously, attempting to access various federal, state, and local government websites. The company did not disclose which government agencies were involved but confirmed that it has reported these incidents to the White House. In a blog post, Anthropic mentioned that one of its AI models under testing had taken several unauthorized actions, including exploiting a vulnerability on a university website to download data and submitting a form to a government agency that it had been explicitly instructed not to submit. The company noted that it discovered these incidents after beginning a review of the AI's actions in July. Earlier on Friday, the Philadelphia Police Department stated that Anthropic had notified them that its technology had submitted a false homicide tip to the police website.

  • No Flights Departing or Arriving at Riyadh's King Khalid Airport Following Explosion Sounds

    On October 10, according to CCTV International News, witnesses reported that explosion sounds were heard at Terminal 3 of King Khalid International Airport in Riyadh, the capital of Saudi Arabia, this afternoon, leading to the evacuation of personnel from the airport. Flight tracking website 'FlightRadar24' indicates that there are currently no flights departing or arriving at the airport, and some flights heading to Riyadh have been diverted or returned. King Khalid International Airport has issued a traveler advisory, recommending that passengers contact their airlines to confirm flight status before heading to the airport.

  • BTC Surpasses $83,000

    Market data shows that BTC has surpassed $83,000, currently priced at $83,020.19, with a 24-hour decline of 0.2%. The market is experiencing significant fluctuations, so please ensure proper risk management.

  • ETH Surpasses $2500

    Market data shows that ETH has surpassed $2500, currently priced at $2500.03, with a 24-hour increase of 0.33%. The market is experiencing significant fluctuations, so please ensure proper risk management.

  • Houthi Forces Claim Saudi Airstrikes on Sana'a Airport in Yemen

    On October 10, according to information released by the Houthi forces in Yemen, on the afternoon of the same day local time, the Saudi-led coalition conducted airstrikes on Sana'a International Airport, which is under the control of the Houthi forces, dropping four bombs. Additionally, the Saudi coalition also targeted a communication facility in Hajjah Province, controlled by the Houthi forces, dropping three bombs. There has been no response from the Saudi side regarding these incidents. (Jinshi)

  • French Finance Committee Approves Amendments on Stablecoin Exchange Tax and Crypto Exit Tax

    On October 10, Decrypt reported that the Finance Committee of the French National Assembly approved two amendments related to cryptocurrency taxation this week: starting January 1, 2027, exchanges of stablecoins regulated under MiCA will be considered taxable sales; and an exit tax will be imposed on taxpayers who have been French tax residents for at least six of the past ten years and have moved abroad with crypto assets totaling over 800,000 euros. On October 9, the committee voted 31 to 3 to reject the budget revenue portion, and the full National Assembly will review based on the government's original text. The amendments will not be automatically included; supporters must reintroduce them during the debate starting on October 13, with a formal vote scheduled for October 20. The related measures have not yet become law. The stablecoin amendment was proposed by Nicolas Sansu, a member of the left-wing GDR party group, along with 16 co-signers, and does not set a new tax rate but aims to include the revenue under France's existing 31.4% flat tax system. The committee also passed an amendment allowing crypto asset losses to be carried forward for ten years to offset future gains.

  • Luxshare Precision: Company and Luxshare Technology Involved in 337 Investigation, Currently in Initial Filing Stage

    On October 10, Luxshare Precision announced that the company and its holding subsidiary, Dongguan Luxshare Technology Co., Ltd., have been listed as respondents in a 337 investigation by the U.S. International Trade Commission (ITC), involving U.S. Patent US 10,903,700. The ITC officially launched the investigation on October 9, 2026, with investigation number 337-TA-1526. The case is currently in the initial filing stage, and no substantial determination has been made regarding the relevant infringement claims. The products involved are in the customer verification stage and have not yet entered mass production.

  • South Korea's Financial Commission: Shareholding Restrictions for Exchange Major Shareholders Not Targeting Specific Companies

    On October 10, Lee Ik-yeon, chairman of the Financial Services Commission of South Korea, stated that the provisions regarding shareholding restrictions for major shareholders of virtual asset exchanges in the ongoing 'Basic Law on Digital Assets' are not aimed at specific individuals or companies. Instead, they are designed to ensure that exchanges, once institutionalized, bear a higher level of public responsibility. Currently, South Korean virtual asset exchanges operate under a system that requires updates every three years, but this will transition to a licensing system after the implementation of the 'Basic Law on Digital Assets.' Lee emphasized that exchanges have infrastructure attributes and must possess public accountability and responsibility commensurate with their status.