There is a significant risk that all of the benefits of quantum computing during the next 20 years will be outweighed by the security devastation caused by quantum computing during the same period. ...He then goes on to explain why quantum cryptography is never going to improve anyone's security.
This brings me to what really bugs me about the Quantum Manifesto. Instead of highlighting the security threat of quantum technology and recommending funding for a scientifically justified response, the Manifesto makes the thoroughly deceptive claim that quantum technology improves security.
A company named ID Quantique has been selling quantum-cryptography hardware, specifically hardware for BB84-type protocols, since 2004. ID Quantique claims that quantum cryptography provides "absolute security, guaranteed by the fundamental laws of physics." However, Vadim Makarov and his collaborators have shown that the ID Quantique devices are vulnerable to control by attackers, that various subsequent countermeasures are still vulnerable, and that analogous vulnerabilities in another quantum-key-distribution system are completely exploitable at low cost. The most reasonable extrapolation from the literature is that all of ID Quantique's devices are exploitable.He explains how quantum cryptography misses the point of what cryptography is all about, and fails to address essential security issues that non-quantum techniques have already solved.
How can a product be broken if it provides "absolute security, guaranteed by the fundamental laws of physics"?
He is right about all this, and I have made similar points on this blog for years.
I also agree, and have said so here, that if quantum computing is successful in the next 20 years, then the social and economic impact will be overwhelmingly negative. The main application is to destroy the computer security that our society depends on.
Where I differ from him is that I say quantum computing and quantum cryptography are both scams, for different reasons. Quantum computing is technologically impossible, and almost entirely destructive if it were possible. Quantum cryptography is possible, but expensive, impractical, and insecure.
Actually, they are both possible in the sense that the laws of quantum mechanics allow experiments such that confirming the 1930 theory can be interpreted as favoring quantum computing or quantum cryptography. But the exitement is about the possibility of super-Turing computing, and more secure key exchanges, but these have never been achieved.