That still leaves a lot of material and much to say. But to appeal to a general audience, a book of this type needs an author who understands the intelligence world and knows how to craft a good story. While ticking the first box, Ferris falls short of the latter requirement. This is a shame because his book is far from uncritical of GCHQ – or the Government Code and Cypher School (GC&CS) as it was known until 1946 – and it explodes a number of myths. But it does so in such detailed, jargon-heavy prose that reading its 700 pages can feel more of a duty than a pleasure.
While he writes glowingly of GCHQ’s transformation into a world-leading player for the cyber age, Ferris provides little evidence to support that claim, even if it’s understandable that the sensitivity of counterterrorist operations must make this hard. Today, he argues, greater openness about intelligence gathering does not affect its relevance and power. His book is an example of this, and shows that the abandonment of Cold War levels of secrecy about GCHQ benefits us all.
GCHQ is proactive in its efforts to recruit women but Ferris does not discuss another of its recruitment initiatives, seeking autistic, dyslexic and other neurodiverse applicants. He does, however, note its liberal social attitudes, such as its understanding and support of the gay mathematician and cryptanalyst Alan Turing, whilst observing that the service was less liberal in its attitude to ethnic minorities in the war years. In tackling these issues, GCHQ shows it is alert to the role of a security and defence agency in a modern democracy, and Ferris is to be congratulated in shedding so much light upon it.
Alas, the book is very much an institutional history, deeply technical in places and largely lacking in colour or human drama. Ferris is no Ben Macintyre – author of a string of non-fiction espionage page turners – or Christopher Andrew, whose entertaining and brick-shaped official history of MI5, The Defence of the Realm, came out in 2009. A drier authorised account of MI6 ends in 1949... Behind the Enigma is a sanitised version of the agency’s history, comprehensive and yet strangely unsatisfying. Donald Trump isn’t mentioned – a counter-intelligence nightmare whose daily brief includes GCHQ material. The modern human stories of those still working on the intelligence frontline have yet to be told.
It is vast, detailed, at times dense and technical, but frequently fascinating. Written with access to the GCHQ archives, it follows the five great sea changes in communications technology: military radio in 1914; mechanised cryptanalysis in 1940; computerised codebreaking from 1955; satellite communications and interception by 1970, and the internet from 1996.... Although some readers may be daunted by the thickets of acronyms and the detailed accounts of bureaucratic manoeuvring, this monumental work completes the authorised picture of a century of British intelligence, a testament to how far Britain has moved away from the cult of official secrecy.