This book is from 1967 and so does not have an isbn number. However i have read another book by this author (my blog) and it begins with the Japanese code breaking based on Arthur Scherbius’s machine.
The early chapters are interesting for the encoding from western to kanji symbols. So knowing Japanese, and knowing radio are two different things.
It is back to the dim and distant past and it admits texts of this statecraft are missing, can cause death and there be dirty jobs Another problem with this special feild is that governments would rather not pay innovators like Hebern*, and cryptanalyst like Yardley who some may liken to Snowden (my blog).
Security requires trust, so when armies loose three safes and a lorry it does make you wonder, and traffic can be traced so while you might not know what is being received you know where they are, and the more sent the further the probability and trace.
An interesting chapter that neither the m15 or m16 (both my blog) do not detail** is the one on censorship although i did know mail was censored, the detailing of its operations is thought provoking, since somebody is thinking about that kind of thing in government even today.
An interesting statistic from 1941, 41% of phone calls where listened to.
The chapter on russian intelligence is most likely fiction the nearer we get to 1967 which is date of publication , and the nsa chapter is also way out of date so read Bamford (my blog), and intelligence collection is expensive.
* can anybody claim that patents reward to inventor ? ** being American helps ?