From Erskine Childers and Joseph Conrad to Ian Fleming and John le Carre, some of the last century's most gripping — not to mention entertaining — fiction has had its roots in the real world of espionage. The history of spying, on the other hand, is frequently a dicey proposition. Even authors with the best of intentions can be misled or partly blinded by their own loyalties or enthusiasms. Those reasonable caveats notwithstanding, Christopher Andrew's Defend the Realm: The Authorized History of MI5 is as complete and thorough as such a history may be and as engrossing as any spy novel.
In part, that's because Andrew, a professor of history at Cambridge, is this era's preeminent historian of espionage. For seven years, he also has been MI5's official historian. The Security Service, as it is called, is Britain's counterintelligence and domestic security agency, roughly equivalent to our FBI.
In this history, it's impossible to not be struck by the different world inhabited by MI5's proto-agent, William Melville, who at the turn of the 20th century entertained his Imperial German counterpart, Gustav Steinhauer — the self-styled "Kaiser's spy," who had trained with the Pinkerton Agency in Chicago — with dinner and cigars at Simpson's in the Strand. Together, they pursued Russian "nihilist" assassins through the London underworld.
The competition with Germany and its intelligence services preoccupied MI5 through World War II. The famed "double cross" operations against the Third Reich and its Abwehr probably represented the Security Service's finest hour.
The Soviets appear to have had the best of the British and the Americans on the Cold War's secret front. They recruited Americans who first spied for politics and later for money. In Britain they sought out the Cambridge aesthetes, who appear to have sold out their country because they'd made an aesthetic of betrayal. Their friends never seemed to notice, because they were amusing and had the right school ties.