Last weekend the movie Enemy of the State was
shown on network television in the US. This is a pretty good thriller
about a rogue NSA official using the resources of the NSA to get back
some evidence from a lawyer innocently tangled up in this affair.
What do we know about the National
Security Agency? While they don't have the best American
mathematicians, who typically go to universities, they have a large
collection of very good mathematicians. While they are free to read
the same papers I read, we hear about very little of their work. They
must have some exciting work in algorithms and complexity I can only
dream about. Perhaps they have an efficient factoring algorithm or a
working quantum computer in their basement. Unlikely, but possible.
Occasionally I meet NSA scientists at conferences, particularly those
meetings devoted to quantum computation. "The NSA is much more
interested in quantum computing than quantum cryptography," one
such scientist told me. This surprised me since quantum cryptography
seems much more likely to have real-world applications than quantum
computers, both in theory and in practice. "The real issue is how
long our current codes will remain unbreakable. We need to know if our
the information currently encrypted will remain safe for 20 or 50
years."
So is Enemy of the State realistic? "Not at all," a
different NSA employee told me at a quantum workshop shortly after the
movie came out. "We work in boring cubicles, not the sleek
offices depicted in the movie." Offices?! What about the satellites
that can track people on the ground in real time? "No comment."