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Revealing Secrets

An Unofficial History of Australian Signals Intelligence & the Advent of Cyber


John Blaxland and Claire Birgin

Randwick, NSW: New South Books, 2023

Paperback    464pp    RRP $49.99


Reviewer: Adrian Catt, September 2023


 This work is an exhaustive and authoritative history of signals intelligence (SIGINT) operations and applications within the Australian context and environment, both strategically and operationally. From its origin in the Boer War in Colonial times, through Federation, peace and wars up to the emergence of the Fourth Industrial Revolution (the Cyber Age), and the resultant current statutory authority, the Australian Signals Directorate (ASD).

Commencing with a brief history as to the origins of codes, codebreaking, cyphers, cryptanalysis and semaphore, (collectively known as SIGINT), the story of the evolution of Australian military units, primarily Navy and RAAF specialising in the collection, analysis and strategic and operational applications from sources such as interception, decryption, traffic analysis and direction finding, is revealed.

Such endeavours have been of huge significance to the protection and administration of Australia and its interests - diplomatically, economically and militarily. The sustained effort to capture the secrets of others, whilst preserving ours, has been built­­-up continually over time, via self-reliance, partnerships, and formal alliances with our trusted Allies.

Moving from telegraph and cable intercepts in the early years, through the wireless age (and the development of radar), the revolution that was the computer age, we are then delivered to the age of being Web-dependent – the Cyber Age. The ramifications, benefits and global entities to which Australia is now cross-dependent make it a valuable contributor to SIGINT over a super-charged Allied network of Geo-stations, satellites and human intelligence, which furnish the protection of Australia around the clock, and assist in the maintenance of a resultant current world peace.

The authors are both highly qualified and experienced to report and comment on these matters, owing to their academic and professional backgrounding, and their use of source material for this outstanding book, which is clearly set-out in the comprehensive Bibliography and also End Notes. This is an excellent source for those seeking to appreciate the value of SIGINT in Australia’s history, or indeed the gestation and emergence of the Australian Signals Directorate.




The RUSI – Vic Library thanks the publisher for making this work available for review.

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