China's quantum satellite link a hack-proof leap forward

Asia Times

17-03-2025

China's first quantum-encrypted link with South Africa marks a breakthrough in ultra-secure communications with far-reaching military and geopolitical implications.
This month, the South China Morning Post (SCMP) reported that China has established its first hacker-resistant quantum communication link with South Africa, a milestone in ultra-secure communications.
Quantum computing employs quantum bits (qubits) to carry out calculations, utilizing concepts such as superposition and entanglement to tackle complex problems at a speed exponentially greater than that of traditional computers.
Unlike the latter with binary bits (0s and 1s), quantum computers can represent and compute multiple states simultaneously, enabling new computation possibilities.
It also provides ultra-secure communications by relying on photons to carry information. Photons' delicate quantum behavior means that any attempt to observe or interfere changes their state, revealing any eavesdropping.
The feat, disclosed during the National People's Congress by Yin Juan, a physicist at the University of Science and Technology of China, involved quantum key distribution over a 12,800-kilometer link, facilitated by the Mozi satellite, launched in 2016.
It marks the first such experiment in the Southern Hemisphere, advancing global efforts to create intercontinental quantum communication services immune to eavesdropping.
The project exemplifies China's strategy to lead in emerging technologies, aligning with its broader innovation and technological self-reliance goals, as emphasized in its 2025 economic plan.
Yin highlighted that secure communications were achieved via low-cost quantum micro-nano satellites and mobile ground stations. The findings are slated for publication in the Nature peer-reviewed journal.
The initiative also reflects geopolitical undertones, with China's aim to integrate quantum communications within the BRICS bloc and achieve global coverage by 2027.
The quantum revelation also comes as the Trump administration cuts aid and assistance to South Africa on the grounds a new law punitively targets Afrikaners on racial lines, an accusation Pretoria has denied. On Friday, in a highly unusual move, the US expelled South Africa's ambassador from Washington.
China's breakthroughs in quantum technology underline its pursuit of global leadership in disruptive technologies, positioning quantum communications as a strategic asset in national defense and economic security.
Delving into the tactical military advantages of quantum technology, in a February 2023 article for the Joint Airpower Competence Center (JAPCC) journal, Michal Krelina and Denis Dúbřavčík mention that quantum technology significantly benefits military air and space domains by enhancing capabilities in sensing, communication and computing.
According to Krelina and Dúbřavčík, quantum sensors, such as quantum magnetometers and gravimeters, enable superior detection of submarines, mines and concealed underground structures, drastically improving intelligence, surveillance and reconnaissance (ISR). They mention that quantum radar and imaging promise higher noise resistance, stealth detection, and target identification, even in adverse environments impacted by fog, smoke or dust.
They say quantum communication, through Quantum Key Distribution (QKD), ensures secure, eavesdropping-resistant communications critical for defense operations.
Additionally, they state quantum computing, though still developing, offers exponential computational speed-up, potentially revolutionizing ISR data processing, machine learning applications and complex aerodynamic simulations​.
Highlighting the technical challenges of military applications for quantum technology, Nelson Roso points out that the most significant among these is operational resilience under harsh conditions.
Roso says quantum systems are susceptible to environmental factors like temperature fluctuations, electromagnetic interference and physical shocks in military settings, jeopardizing the stability of fragile quantum states.
Another substantial hurdle Roso points out is interoperability with legacy communication systems, necessitating extensive adaptations to merge delicate quantum signals seamlessly with classical infrastructures without compromising security or efficiency.
Additionally, he says there are complexities related to quantum network design, including overcoming inherent distance limitations of QKD through quantum repeaters and quantum satellites to ensure robust and secure global military communications.
At the operational level, Daniel Choi mentions in a September 2023 Expeditions article that quantum satellite technology improves military operations by providing secure and nearly unbreakable communication through QKD, which detects any interception due to the principles of quantum physics.
Choi says quantum communication networks could integrate geographically dispersed military units with unprecedented security, enabling coordinated operations free from cyber espionage threats.
Additionally, he says quantum inertial navigation systems, independent of vulnerable GPS signals, promise exceptional accuracy, ensuring precise positioning even in GPS-denied environments. Such advances drastically improve coordination and situational awareness, significantly reducing response times to global crises and transforming strategic capabilities beyond regional boundaries.
In a 2021 article for the Sensors peer-reviewed journal, David Gozzard and other writers mention that in a hypothetical attempt to interfere with a quantum communications satellite, a ground-based laser with a moderate power of 1 kilowatt can inject excess noise photons into a satellite's QKD channel, severely increasing the quantum bit error rate (QBER) to levels that prevent secure key generation.
They note that photons from these lasers scatter off satellite surfaces, particularly those covered with reflective materials, introducing sufficient noise into the ground-based QKD receiver.
They say this completely disrupts key generation, as demonstrated by modeling based on the Chinese Mozi satellite design, signaling a serious threat to future satellite-based secure communications.
However, Gozzard and others note that quantum communications satellites could be designed to minimize reflection and light scattering, requiring ground-based lasers to increase their output to impractical levels to achieve interference.
Laurent de Forges de Parny and other writers mention in a January 2023 article for the Communication Physics peer-reviewed journal that optical data links between quantum satellites and their ground stations are affected by atmospheric phenomena such as clouds, aerosols and atmospheric turbulence.
At the strategic level, China's push to integrate its quantum technology within the BRICS bloc aims to secure its influence over the latter by influencing technology standards, strengthening strategic partnerships, and enabling power projection.
Joseph Kurlantzick mentions in a March 2023 Council on Foreign Relations article that China aims to control the 'pipes' of information, such as global information networks, including their associated physical infrastructure and norms.
Kurlantzick argues that China, with control of information pipes, could use them to spread favorable narratives while censoring negative ones. He says this could enable China to export its alternative views of international relations based on non-interference in other countries' internal affairs.
He argues that China could use such influence to help foreign countries copy China's vision of a closed and controlled domestic internet, mimicking China's technology-enabled authoritarianism.
Further, in an April 2023 Heritage Foundation report, Dustin Carmack discusses the quantum arms race between the US and China, emphasizing the national security implications of quantum technology.
According to Carmack, the US is leveraging a whole-of-government and whole-of-industry approach to maintain leadership, while China has aggressively invested in quantum computing, encryption and communication. He says China's advancements in quantum cryptanalysis directly threaten US encryption, potentially enabling it to decrypt sensitive data.
As quantum computers use qubits, they can test multiple mathematical solutions simultaneously, quickly solving the complex math needed to crack contemporary encryption algorithms that would take traditional binary computers billions of years.
Carmack mentions the US has responded by blacklisting Chinese firms, expediting post-quantum encryption and fostering international collaborations. He argues that the quantum race will define global power dynamics, with military, cybersecurity and economic dimensions shaping the 21st-century geopolitical landscape.