How quantum computers will speed up the breaking of public-key cryptography and how “post-quantum cryptography” researchers are trying counter that threat
Joshua Holden / Nautilus :
Context & Ripple Effects
This early-2018 Nautilus explainer by mathematician Joshua Holden laid out the core problem years before it became policy: sufficiently powerful quantum computers would break the public-key cryptography underpinning RSA-style encryption, and a research field called post-quantum cryptography exists to replace it. At the time, the piece was framing a distant hypothetical.
The subsequent coverage shows the arc Holden's article anticipated: by late 2020 the competition to develop new encryption standards against quantum attacks was underway, US agencies were by 2021 preparing defenses against attackers who harvest data now for decryption later, and by 2026 a cryptography engineer was calling the risk of inaction unacceptable following Google's warning.
First-order effects
- Holden's explainer gives the general technical audience its map of the threat — which public-key methods fall to quantum algorithms and which post-quantum alternatives researchers are pursuing — feeding directly into the standards competition the Wall Street Journal later documented.
Second-order effects
- Once the threat model is widely understood, institutions act on it: US agencies began preparing post-quantum migrations against 'harvest-now, decrypt-later' attackers (MIT Technology Review's reporting on agency preparations) because data encrypted today remains exposed once quantum machines mature.
Third-order effects
- If the pattern holds, the industry moves from treating quantum resistance as a research topic to an operational mandate — as Filippo Valsorda's call for an urgent rollout of quantum-resistant cryptography after Google's warning shows — with replacement of public-key infrastructure becoming a multi-year engineering program rather than an academic exercise.
The trend: Public-key cryptography is on a path from theoretical quantum vulnerability toward mandated quantum-resistant replacement, with the gap between academic warning and operational urgency steadily compressing.