Every two decades or so, a new technology upends national security. In the 1940s and 1950s, the atomic and hydrogen bombs established nuclear deterrence. In the 1970s and 1980s, microelectronics led to the creation of stealth and precision weapons and early digital networks. In the 1990s, the Internet and the deployment of the Global Positioning System (GPS) remade communications. Now, of course, artificial intelligence is powering autonomous weapons and supercharging cyber-capabilities, but soon, it will be quantum technologies that transform myriad areas from exposing national security secrets to projecting military power.
Quantum technologies work by leveraging the strange behavior of extremely small particles. They can therefore do things that conventional technologies can’t, such as precisely measuring location while entirely offline and, in theory, cracking encryptions that are widely used today. A classical supercomputer would need roughly 300 trillion years and “brute force” to break a common encryption, known as a 2048-bit RSA key. A quantum computer, by contrast, could theoretically decrypt that same key, which is used to protect medical records, financial transactions, and state secrets, in under eight hours. Innovations in the field of quantum sensing will soon enable armies to operate in “GPS denied” environments, where satellite signals are blocked, disrupted, or unavailable.
Although this future seems far off, it is not. According to reports from U.S. intelligence agencies, the United States’ adversaries are already harvesting encrypted U.S. data in the hopes that once they acquire quantum capabilities—be it in five or ten years—they can read it. China especially is investing in quantum communications and encryption tools. Washington and its allies need to do everything in their power to win the quantum race while also preparing for a world in which Beijing or Moscow builds a quantum computer first. Most urgently, this means encrypting today’s secrets with more advanced cryptography that can’t be cracked in the future.
A QUANTUM LEAP
Because quantum computing has the potential to crack the encryption most broadly used by governments and individuals alike, the threat that it poses to national security is difficult to overstate. The cryptography that secures much of the Internet today relies on the difficulty that conventional computers have solving certain math problems, such as factoring very large numbers. Quantum computers, however, are expected to perform some of these computations far more efficiently, enabling attackers to break the codes and seize sensitive data.
No such machines exist yet, and it is difficult to predict when they might come online. But recent advances suggest that a quantum computer could break at least some forms of commonly used cryptography within the next few years. More important, rivals of the United States are not waiting around for a quantum computer to materialize. China and Russia have already collected encrypted U.S. secrets, betting that some of the information will still be relevant once they have the tools to decrypt it.
The implications of quantum technologies for national security extend beyond cryptography. Quantum sensors can measure time and differences in gravitational and magnetic fields with unprecedented sensitivity and accuracy. These sensors could eventually be used to detect stealth vehicles or navigate armies through GPS-denied environments. That is especially useful for the United States because China is making strides when it comes to jamming GPS, which the U.S. military and its allies depend on for precision-guided munitions and drones. Historically, if a country jammed GPS, which is owned and operated by the U.S. government, it risked disrupting its own forces, but China now has its own BeiDou-3 navigation constellation of satellites, which allows it to deploy powerful GPS jammers across theaters, such as the South China Sea, while its assets remain operational. Quantum sensors, however, offer a path to get around China’s system because they provide a local source of precise positioning and timing that does not depend on GPS or any satellite signal.
So far, when it comes to quantum, the United States maintains a technical edge in hardware, and much of its progress is driven by private companies, including IBM, Google, and various startups. China, by contrast, has identified quantum as one of its top priorities in its five-year plan for 2026–30 and centralizes most of its research and development under state-directed hubs, such as Hefei National Laboratory. Although China’s initial investments focused on building a secure quantum communications network, the country has also made strides in quantum computing over the last few years, and it is already developing quantum sensors for its submarines and stealth aircraft, motivated by the prospect of systems that both leapfrog traditional technologies and are unencumbered by current export controls.
The quantum threat to national security is difficult to overstate.
With the U.S.-Chinese rivalry moving beyond the realm of pure research to include multibillion-dollar investments in specialized hardware, competing technology blocs are also emerging. The United States, for example, has joined leading quantum allies such as France, Japan, and the United Kingdom to form the 13-nation Quantum Development Group, with the aim of securing global supply chains and protecting national security interests from emerging quantum threats. China, meanwhile, is already collaborating with BRICS countries, most notably Russia, which is home to world-class physical science, math, and cryptography capabilities.
Little information is publicly available about Russia’s quantum efforts. Although the country is focused on developing military tools for the war in Ukraine, it is already advanced in developing algorithms for encryption, which might help it build a smaller, but still capable, quantum computer. Since its full-scale invasion of Ukraine, in 2022, Russia has forged closer ties with China. In late 2023, the two countries demonstrated what they called “a secure quantum link,” transmitting information instantly between Chinese satellites and Chinese and Russian ground stations 2,400 miles apart with ostensibly zero risk of eavesdropping. (Because quantum communications rely on the physical properties of quantum particles, the very act of eavesdropping disturbs the signal, instantly alerting both parties that the communication has been compromised.) In early 2025, China conducted a similar demonstration with South Africa linking stations that were over 8,000 miles apart.
Scientists in the United States and Europe question the value of these technologies because they require traditional encryption to authenticate both ends of the link and therefore still have vulnerabilities. Nevertheless, these demonstrations with fellow BRICS members suggest that Beijing may be laying the groundwork for broader quantum cooperation within the bloc, perhaps extending to computing and sensing, as well.
CODE CRACKERS
Washington has already begun to take steps to prepare for a world in which its adversaries possess quantum technologies. Beginning in 2016, cryptographers around the globe competed in a U.S. National Institute of Standards and Technology project to develop new algorithms capable of resisting a quantum computer attack. In August 2024, the institute standardized an initial set of these algorithms, which large Internet infrastructure firms began deploying internationally. Every major Internet company, including Google and Facebook, uses quantum-resistant cryptography to some extent. But these new standards have yet to be extended to other Internet protocols, including the systems that certify websites as safe to use. The U.S. government has said that all federal agencies will use quantum-resistant cryptography by 2035, but it is possible that quantum computers will crack government encryption ahead of that deadline. A recent paper from Google suggests that breaking a type of cryptography that secures most Internet communications may require far fewer resources than previously thought. Google has accelerated the timeline on which it will upgrade to quantum-safe cryptography to 2029, urging others to follow.
Even if the transition to these quantum-proofed algorithms is completed before the invention of a fully capable quantum computer, the massive amount of sensitive material that China and Russia have already harvested will probably be compromised. Of course, some of the information that is collected now will be useless by the time they can decipher it. The position of U.S. troops today, for example, will have changed by 2030. But other highly sensitive information, including nuclear design secrets, will be relevant for a long time and poses the largest risk if amassed, and eventually decrypted, by adversaries.
To address quantum’s national security challenges, the United States and its allies must begin by securing a domestic “quantum stack”—thereby ensuring that the hardware, materials, and intellectual property required for quantum technologies remain within their direct control. The United States should use export controls to protect the specialized electronics, refrigerators, helium, and silicon isotopes that make up quantum technologies. U.S. and allied intelligence agencies must also prioritize protecting private-sector quantum intellectual property from industrial espionage by sharing threats and cybersecurity advice with U.S. and allied companies and requiring firms to deploy top-tier cyberdefenses.
Quantum sensors could eventually be used to detect stealth vehicles.
But that is not enough. The United States must also lead a truly global effort to upgrade all Internet protocols to quantum-resistant encryption. Even if just one country uses a lower encryption standard, it creates a weak link in global trade. To that end, the U.S. National Institute of Standards and Technology must lead a cooperative effort with the European Union Agency for Cybersecurity and equivalent bodies in Asia to develop interoperable algorithms—and then share such algorithms and technical assistance with developing countries.
Still, these solutions assume that it will take years for anyone to invent a quantum computer sophisticated enough to crack today’s encryption. If, however, one is developed in the short-to-medium term, it will threaten the security of current systems and information that was transmitted in the past. To deal with the possibility of such a disruption, governments and companies should immediately compile inventories of the data that has already been exposed in vulnerable channels and determine which presents the highest risk if deciphered in a few years’ time. Organizations should then prepare for likely disclosure, making contingency plans to protect the assets potentially exposed.
One important category of secrets are credentials, such as passwords or authentication keys. If an attacker decrypts a connection containing these credentials, they can then be used to remotely access sensitive systems even if those systems subsequently deploy quantum-resistant encryption. Once a company or government establishes more advanced encryption, all previous passwords and authentication keys need to be changed. Governments and leading digital infrastructure companies must also prepare for the possibility that a sophisticated quantum computer is developed before all Internet protocols adopt quantum-resistant encryption. In that case, governments must come up with contingency plans for an emergency transition or risk significant disruptions to industries that rely on secure transactions. These plans might include rapidly deploying quantum-resistant encryption to key sectors, such as banking and communications, and abandoning connectivity to systems that have not yet upgraded.
Although competition between the United States and China over quantum technologies will be fierce, the two countries recognize that they need to work together through bodies such as the International Organization for Standardization and the Internet Engineering Task Force to ensure that their foundational protocols are interoperable. Both countries are keen to avoid a fragmented digital world in which global commerce and logistics are disrupted by incompatibility. Indeed, Chinese cryptographers took part in the U.S. government’s global contest for algorithms, and American and European researchers did the same in China’s open competition. But such cooperation will probably never extend to matters of hardware. When it comes to technologies that have military applications, each great power will be determined to dominate the other.
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