Calder Walton’s epic story of the espionage war between East and West is, first and foremost, fascinating.

He covers the subject thematically, treating each major theme in roughly chronological order, except where departure from strict chronology aids in understanding. The author clarifies when and why this is happening.

A key theme of the book is that the intelligence conflict is a clash between authoritarianism and liberal democracy, and authoritarian regimes have key advantages. Their intelligence services are not subject to the rule of law, strict oversight, accountability for mad designs, or morality. Operational effectiveness is the only consideration, as evidenced by the assassination at by Russian GU agents of a troublesome dissident by radioactive poison, resulting in the collateral irradiation of dozens of innocent people.

This is not to say that Western intelligence services have not had their own fiascos, such as meddling in elections in Central and South America, to the great detriment of all concerned, including the US, due to US leadership’s myopic fixation on Communism. Similarly, after 9/11, the author makes the point that a fixation on kinetic counter-terrorism gave authoritarian actors room to maneuver freely and largely unobserved by the West.

As a normal American, I am perhaps susceptible to the illusion that our society is secure, our values universal, and our enemies far away. This book disabuses the reader of such illusions, carefully and painstakingly walking through the astonishing breadth of the intelligence efforts brought to bear against us, from spies in key positions in US and British intelligence to Soviet/Russian meddling in elections to the Chinese whole-of-society approach to intelligence gathering.

Did you know that Chinese law requires companies to disclose to the CCP information gained from their overseas business dealings upon request? I didn’t. That changes the entire scope of the enterprise.

Speaking of scope, the book points out that the KGB at its height employed 420,000 people, and the Chinese MSS employs close to double that number.

Western intelligence services are minuscule by comparison, although it is worth pointing out that much of the manpower (and it is almost all men in the services of our authoritarian rivals) is devoted to suppressing the local population and keeping the regime in power, rather than deployed overseas.

Where lies the future of intelligence? The author convincingly argues that the future is in cyber, with human espionage a niche element. Personally, I think he overstates the point, and that the cyber realm merely extends the reach and speed of the same signals intelligence, electronic intelligence, disinformation, and spycraft that have always defined the intelligence landscape.

The book is not perfect, as other reviews have pointed out. As a monument to prose, it falls short, though that was never the author’s purpose.

There were also places where the author provided statements or conclusions that seemed startling and important, but frustratingly refrained from providing additional analysis or details. Whether this was due to constraints of space (the book is large, as is), or due to the paucity of publicly available information, or because state secrets laws precluded going into further detail, sometimes, the book left me wanting more.

The author does have a website where those interested may browse for further detail. But, websites come, and websites go, and there is no telling how long that resource will remain available.

Despite these relatively minor flaws, SPIES changed the way I perceive the geopolitical landscape and international relations, and it changed the way I perceive the social bubble that I personally inhabit.

I offer a heartfelt thank you to the brave professionals of Western intelligence agencies, and to those agents who have turned against authoritarianism at great personal risk, for all that they have done and continue to do.

Highly recommended.