Her Majesty's Secrets Revealed

David Bebber / Reuters A new history of MI5 contains revelations straight from the spy agency's files, from bungling the Irish troubles to Hitler's thoughts on Chamberlain.

There are some books that Kindle just doesn’t do justice to. Defend the Realm: The Authorized History of MI5 by Christopher Andrew is one such tome. On a Kindle it becomes just another electronic file. But its size—over a thousand pages, and packed with more than 4,000 source notes and references to over 500 other books, size tells you this was no ordinary undertaking.

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Defend the Realm, a decade-long project for Andrew, a Cambridge professor and the person widely recognized as England’s leading historian of intelligence, is an authorized history. Andrew received unprecedented access to MI5’s files. Intelligence agencies don’t usually open their doors to independent historians. Nor does MI5’s director write many introductions for books, as he does here.

Defend the Realm: The Authorized History of MI5. By Christopher Andrew. 1056 pages. Knopf. $40. But “authorized” doesn’t necessarily mean whitewash. While the book is not intended as a hard critique, there are plenty of fresh details about celebrated events, behind the scenes tidbits about successes and foibles, and dish about infamous people. Even the 32 pages of photographs, many from MI5’s archives, have never before been published. Defend the Realm (from MI5’s Latin motto, “regnum defende”), traces MI5’s growth from a staff of two in 1909 to today’s 3,000-plus agents and employees. It’s crack for history and spy agency addicts.

One of the best parts is proving once again the old adage “those who do not remember past mistakes are doomed to repeat them.” This was especially true when it came to a series of British intelligence failures in Northern Ireland during the 1970s. MI5 and the chief spooks operated as if they had no sense of the history of Irish troubles and made remarkable errors in failing to coordinate policies between the police, the military, and the intelligence agencies. The resulting chaos cost lives and extended the IRA’s reign of terror. The often bitter internecine competition between MI5 and other British intelligence departments over the IRA terror campaign is reminiscent of the crippling FBI-CIA rivalry over Islamic terrorism that led to the two American agencies repeatedly crossing wires in the lead up to 9/11. MI5’s files reveal how brilliantly the agency fought Hitler by capturing most of the Nazi spies in Britain and turning 25 of them into double agents. But it struggled against Cold War Soviet espionage and failed miserably early on to grasp the threat posed by Islamic extremism. The book discloses that the agency's then-chief, Stella Rimington, had never even heard of al Qaeda until a 1996 meeting in Washington, during which MI5 agents were visibly ''taken aback by the [American] interest'' in Osama bin Laden.

Its terror fighting efforts since the September 11 attacks have been mixed. While it failed to stop the July 7, 2005, transit bombings that killed 52, it has also had a string of successes, including exposing/stopping the plan to blow up trans-Atlantic airliners using liquid explosives (yes, air travelers, you have MI5 to blame for having to put all your liquids into 3 ounce containers every time you pass through airport security). Andrew reveals that in 2000, MI5 unwittingly foiled a plot by al Qaeda to obtain biological weapons when it discovered samples and testing equipment in the luggage of a Pakistani microbiologist, Rauf Ahmad, who had attended a conference about pathogens in Britain. The CIA later revealed that Ahmad had been in touch with al Qaeda's No. 2 man, Ayman al-Zawahiri.