Quantum computer threats are approaching? Bitcoin faces long-term risks, with more severe short-term challenges

The Saudi Arabian government-controlled energy company Saudi Aramco recently deployed its first quantum computer domestically, once again raising concerns within the crypto community about the so-called “Q Day”—the moment when quantum computers become powerful enough to derive private keys from public keys and forge digital signatures. This 200-qubit system, manufactured by French neutral atom quantum computing company Pasqal, marks another milestone in the global quantum computing race and has reignited doubts about the security foundations of digital assets. However, despite the impressive development of quantum computers, how far are we from a threat that could truly impact Bitcoin?

When Will the Quantum Computing Threat Truly Arrive

According to an analysis on a blog by Scott Aaronson, a professor of computer science at the University of Texas at Austin, given the current rapid hardware development pace, it is “very likely” that a fault-tolerant quantum computer capable of running Shor’s algorithm will be built before the 2028 US presidential election. Shor’s algorithm is a quantum algorithm used for integer factorization—and this is precisely what threatens modern cryptography.

Ethereum co-founder Vitalik Buterin also recently warned that quantum computers could threaten the very foundation of cryptography—elliptic curve cryptography. This encryption method is widely used in Bitcoin and other blockchain networks. Once quantum computers become powerful enough to crack such encryption systems, attackers could reveal private keys, forge signatures, and thus steal funds or undermine privacy protections.

“Someone with a quantum computer could authorize a transaction to transfer all your Bitcoin without your permission. That’s the scariest part,” said Justin Taylor, associate professor at Georgetown University and partner at Anderson Horowitz Foundation. This risk not only threatens cryptocurrencies but could also impact many security systems supporting the global economy.

Christopher Pettet, a professor of computer science and engineering at the University of Michigan, pointed out that “there is a significant (over 5%) probability that quantum computing will pose a major or even existential long-term risk to Bitcoin and other cryptocurrencies. But in the next few years, this is still difficult to constitute a real threat.”

The Technical Barriers Still High: Cracking Bitcoin Requires Millions of Qubits

Although quantum computers are developing rapidly, overcoming the enormous technical hurdles to truly threaten modern cryptography remains a challenge. Pasqal’s 200-qubit system may seem large, but in practical applications, its scale is relatively limited. Researcher Ian McKellar explained that 200 qubits are enough for some interesting experiments and demonstrations, but even with such a number, due to noise and short coherence times, large-scale error correction calculations are difficult to realize.

Running Shor’s algorithm specifically requires this kind of high-precision computing power. California Institute of Technology graduate student Eli Battaye pointed out that to threaten modern cryptography, a quantum computer needs “very long coherence times, far exceeding the duration of operations.” In other words, an attack-level quantum computer would require thousands of logical qubits, equivalent to millions of physical qubits.

In comparison, Google’s recent 105-qubit Willow chip and the 6,000-qubit neutral atom system announced by Caltech in September are still well below the attack threshold. These machines are mainly used for research, simulation, and algorithm development, not cryptographic attacks. Experts generally believe that in the coming years, the threat of quantum computers to cryptography remains a distant risk.

Bitcoin Faces More Urgent Short-Term Challenges

Compared to the distant threat of quantum computing, Bitcoin currently faces much more immediate market pressures. According to the latest data, Bitcoin is trading at $90.29K, down 0.80% in the past 24 hours, with a circulating market cap of $1803.97B. Ethereum is at $3.00K, down 1.16% in 24 hours, with a market cap of $362.43B.

Recently, Bitcoin market capital has been continuously flowing out, with institutional investors especially selling off. Market data shows that Bitcoin ETF fund outflows have hit new highs, reflecting that institutional investors have stopped allocating to Bitcoin and are instead selling. “ETF institutions have become sellers; as long as they keep selling, the market will find it hard to sustain upward movement or rebounds,” said Marcus Tull, founder and CEO of 10X Research.

Cryptocurrency companies heavily reliant on coin value growth are under even greater pressure. Many firms that accumulated large amounts of crypto assets to bolster their treasuries are now facing a double hit to stock prices and coin prices. To support falling stock prices, these companies are forced to sell their holdings of digital tokens. Retail investors are also defensive, with the number of wallets holding large amounts of Bitcoin increasing more slowly, while small wallets continue to decrease.

Technical Analysis: Key Support and Resistance Levels

From a technical perspective, market analysts generally see $90,000 as a critical threshold. Beimnet Abebe, head of credit trading at Galaxy Digital, believes that the top of this cycle is likely already established, and in the short term, prices will struggle to return to the $120,000–$125,000 range.

According to Coindesk analysis, Bitcoin first needs to break through the resistance of the 200-hour simple moving average (SMA), currently near $88,000. The next resistance zone is between $98,000 and $99,000, an area that has previously formed intraday lows multiple times recently. The most critical support level is around $83,680; if broken, it would send a clear risk signal, potentially leading to deeper declines. The next support level is approximately $74,500.

Delphi Digital analyst presented two scenarios: in an optimistic case, the market could rebound after a correction and break through $103,500; in a pessimistic case, the rebound might be blocked between $95,000 and $99,000, followed by a drop to around $75,000. Even Arthur Hayes, who has always been bullish on Bitcoin, has changed his stance, now believing Bitcoin will stay below $90,000 and may retest the $80,000 level.

Of course, not all voices are pessimistic. Yierhua, founder of Liquid Capital, believes that based on research data, Ethereum is under multiple short positions, but after passing the toughest period, a short squeeze could follow. Compared to four years ago, infrastructure such as stablecoins, ETFs, and policies has matured, and Ethereum’s price may be seriously undervalued.

The Double Play of Long-term and Short-term Risks

The threat of quantum computers does exist, but the consensus among experts is clear: this is a long-term risk, not an immediate threat. Currently, the most advanced quantum systems still face multiple technical bottlenecks such as coherence time and error rates, and are still far from being able to attack cryptography effectively. The requirement of hundreds of thousands of qubits means this race will continue for many years.

In contrast, Bitcoin and the crypto market face tangible, immediate challenges—capital outflows, declining market sentiment, institutional selling. Until these real pressures dissipate, the threat of quantum computers may continue to be overlooked by market participants.

For the blockchain industry, it’s a balancing act—preparing for future quantum threats while managing current market challenges. It is this balance between long-term planning and short-term realities that will shape the future development trajectory of digital assets.