[grkvlt]

Of course governments must keep secrets. These are things like order of battle details for the military; location and other details for nuclear weapons; names and addresses of intelligence officers, informants or defectors; algorithms for decryption of foreign ciphers; and so on. However, in western democracies the secrecy is usually time limited. For example in the United Kingdom we have the 30-year rule[0] which provides for public release of confidential government documents after 30 years (and they are moving to 20 years now) which is a good compromise between transparency and the need for operational secrecy and security.

0. https://en.wikipedia.org/wiki/Thirty-year_rule