[nobody3141]

It has do with paranoia and a government and civil services that have managed very nicely for 200years by automatically keeping all successes and failures secret.

GCHQ invented public key encryption in the 70s years before RSA. But instead of publishing it and making money for British companies and giving British citizens a way to keep their money safe they kept it secret. Note, that keeping the invention secret doesn't improve the security of any data encrypted with it.

They were given permission to publish it in the late 80s - a decade after it was making lots of money for R,S and A. But the permission was pulled at the last minute because the publishing of Spycatcher was proving embarrassing for the government and the natural knee jerk reaction was to keep everything - however tangentially related - secret again.

[dfc]

What was the name of the GCHQ cryptosystem? Any reference links?