Sizing up the quantum threat to cyber security: Making sense of quantum computing headlines
Abstract
Quantum computing is predicted to pose a critical threat to traditional public-key cryptography and weak forms of symmetric cryptography if a massive-scale ‘cryptographically relevant’ quantum computer (CRQC) is successfully developed at some future point. Sensationalised headlines reflect fluctuating hype over these emerging technologies and present a distinct challenge for cyber security professionals outside the quantum computing research and development (R&D) space to rationalise. This paper offers a practical scaffold for making sense of headlines about quantum computing progress and its potential significance for cyber security. Context is offered on the wide range of quantum computers being developed and key challenges they have yet to surmount, the ambiguous terminology and uncertain milestones benchmarking quantum computing progress to date, key assumptions that underpin the spectre of a so-called ‘Q-day’ cyber security crisis scenario, and the wide distribution of expert opinion about the quantum computing future. Cyber security professionals are counselled to exercise a healthy caution in their read of quantum computing headlines, but to pursue prompt migration towards quantum-safe standards as part of a broader focus on system-wide cyber resilience. This article is also included in The Business & Management Collection which can be accessed at https://hstalks.com/business/.
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Author's Biography
Briana Bowen co-founded and currently serves as adjunct faculty for the Center for Anticipatory Intelligence at Utah State University, an interdisciplinary centre focused on complex emergent security issues and the first US degree-granting programme in anticipatory intelligence. Briana stepped down as CAI’s Associate Director in 2023 to pursue a PhD in information security (CDT) at Royal Holloway, University of London, UK. Briana has served as co-PI of a Minerva Research Initiative grant focused on human governance implications of emerging artificial intelligence applications, supported research on multiple US federally funded projects relating to strategic culture and security issues, and is a co-editor of the ‘Routledge Handbook of Strategic Culture’ (Routledge, 2023). Her current research and teaching focuses concentrate on anticipatory narratives around quantum computing, forecasting and foresight methodologies, weapons of mass destruction, Russian security affairs and the US–UK ‘special relationship’. Briana holds a BA in political science from Utah State University and an MPhil in Russian and East European studies from the University of Oxford.
Keith Martin is a Professor of Information Security at Royal Holloway, University of London, UK and director of the EPSRC Centre for Doctoral Training in Cyber Security for the Everyday. He has broad research interests, with a focus on application of cryptography and geopolitical aspects of cyber security. Keith holds a degree in mathematics from the University of Glasgow and a PhD from Royal Holloway. Following research positions at the University of Adelaide and the Katholieke Universiteit Leuven, Keith returned to Royal Holloway in 2000, where he co-created the successful distance learning MSc in information security, and served as Director of the Information Security Group from 2010 to 2015. Keith has over 100 research publications in cyber security, as well as articles in the popular and professional press. He is author of the textbook ‘Everyday Cryptography’ (OUP, 2025), now in its third edition, and the popular science book ‘Cryptography: The Key to Digital Security, How it Works and Why it Matters’ (Norton, 2020). He has also presented courses on cyber security to a wide range of audiences, including specialist industrial short courses, the general public and schools.
