We have way too many secrets in government.
Agree completely, but the lip service paid to protecting national security is appalling: Sandy Berger comes to mind.
As a Platoon Leader back in 77-79, we carried a pamphlet sized document called a CEOI, which had frequencies and call signs to be used during field exercises.
It was classified "confidential", but it might as well been classified beyond NATO Top Secret. If you lost one out in the field, your career was over. Saw it happen to a West Pointer. We secured it to our bodies with a chain or lanyard, but stuff happens out in the field.