More than three decades after Peter Shor published the algorithm that bears his name, the question of when, not if, a large-scale quantum computer will break much of the world’s encryption has shifted from theoretical to logistical. In an interview with New Scientist at the Quantum.Tech World conference in Boston, Shor offered a characteristically clear-eyed assessment.
“We have good methods for post-quantum cryptography, we just have to implement [them],” Shor said. “This will be incredibly hard.”
The difficulty, Shor explained, is not cryptographic. The National Institute of Standards and Technology (NIST) has already established quantum-proof encryption standards. The challenge is institutional: large organizations, banks, hospitals, government agencies, will need years to audit every cryptographic endpoint in their networks, update every device and piece of software, roll out new protocols, and ensure backward compatibility without breaking critical infrastructure.
The 2029 and 2031 deadlines
Two dates focus the migration timeline. Google has set an internal target of 2029 to complete its own migration to post-quantum cryptography across all its products and infrastructure: search, cloud, Gmail, YouTube, Android. It is a proactive, self-imposed deadline signaling that the company believes a sufficiently powerful quantum computer may be viable within that timeframe.
In June 2026, U.S. President Donald Trump signed an executive order mandating that all high-value and high-impact U.S. government systems must migrate to post-quantum cryptography by 2031. The order covers national security communications, federal financial systems, healthcare data infrastructure (Medicare, VA, HHS), critical infrastructure (energy grid, transportation, water), and intelligence community systems, any system whose compromise could cause catastrophic harm.
Still toys, but not for long
Shor described current quantum computers as “still toys, but they’ll stop being toys very soon.” The progress in making quantum hardware bigger and more reliable has been “incredible,” he acknowledged, but practical applications remain limited.
He sees genuine value in one specific domain: simulating quantum systems and molecules for chemistry and biomedicine. He also believes optimization algorithms may have been dismissed too quickly by the research community.
But he dismissed broader claims about quantum computers as general-purpose supercomputers. “I don’t think that quantum computers will help predict the stock market,” he said flatly.
The puzzle of the missing algorithm
Perhaps the most intriguing part of the interview is Shor’s reflection on the state of quantum algorithms themselves. Since his 1994 discovery at Bell Labs, an algorithm that can factor large integers exponentially faster than any known classical method, threatening the RSA encryption that underlies secure communications, no one has found another quantum algorithm with comparable impact. Despite billions of dollars in research funding and decades of effort, Shor’s algorithm remains the single most powerful known quantum algorithm for cryptographically relevant problems.
Shor offered two possible explanations. Either researchers simply “haven’t been smart enough yet” to find the next major algorithm, or quantum computers are fundamentally not useful for most problems, a possibility that many in the field prefer not to confront directly.
“But you have to understand all of quantum mechanics and all of computer science, and that’s really a lot to learn,” Shor said of the difficulty of finding new quantum algorithms.
The real race
The interview clarifies that the race in quantum computing is no longer solely about whether fault-tolerant quantum computers can be built; that is increasingly assumed. The race is about whether the migration to post-quantum cryptography can be completed before one is built that can run Shor’s algorithm at scale. The cryptography is ready, Shor says. The question is whether the world’s institutions can move fast enough.
Sources
1. New Scientist, “Peter Shor’s algorithm could break the internet, but he’s not worried” (7 July 2026). https://www.newscientist.com/article/2533218/peter-shors-algorithm-could-break-the-internet-but-hes-not-worried/
2. Shor, P.W., “Algorithms for quantum computation: discrete logarithms and factoring”, Proc. 35th Annual Symposium on Foundations of Computer Science (1994). DOI: 10.1109/SFCS.1994.365700