Enemies: a History of the FBI by Tim Weiner: review Five years ago, Tim Weiner wrote an award-winning book about America's Central Intelligence Agency. He described an institution that was amoral, out of control and incompetent: it was a brilliant demolition job. This month sees the publication of Weiner's follow-up: a history of the CIA's equally scary cousin, the Federal Bureau of Investigation. The FBI, he shows, has indulged in much of the same behaviour as the CIA - illegal spying, burglaries, black propaganda, even the installation of puppets in neighbouring governments - only it did it better, and was more efficient at covering its tracks. There are stories here to make supporters of civil liberties apoplectic. For example, Martin Luther King was placed under surveillance throughout the Sixties, while the Ku Klux Klan was targeted only as an afterthought. The FBI waged a war on gay people in government and ruthlessly purged anyone with even moderately Left-wing views from the foreign service. It interned and arrested people en masse without any evidence of wrongdoing, blackmailed members of the government and routinely disobeyed instructions from the president and Congress. Under J Edgar Hoover's 48-year reign, the FBI was a law unto itself, and more than one president compared it to the Gestapo. "No holds were barred," admitted Bill Sullivan, the bureau's head of counterintelligence during the late Fifties. "Never once did I hear anybody, including myself, raise the question: "Is this course of action which we have agreed upon lawful? Is it legal? Is it ethical or moral?" " Another agent put it more succinctly: "Nobody knew what was right or wrong." The FBI was the closest thing that America had to an Eastern European-style secret police. And yet, for all his outrage, Weiner stops far short of condemning the bureau. Its behaviour was not the result of megalomania, he claims, but of a genuine desire to keep the nation from harm. In the words of Mark Felt, the bureau's second-in-command in the mid-Seventies, "you are either going to have an FBI that tries to stop violence before it happens or you are not." The bureau's true crime, Weiner implies, is not that it trampled on civil liberties, but that it made mistakes. The consequences of these mistakes started to become apparent only after Hoover's death in 1972. After a series of devastating scandals that exposed FBI excesses, its powers were reined in, just as America was coming under attack from a new quarter. In the decades that followed, the FBI was directed by a series of flawed leaders who proved unable to restore its self-belief, or to reform its stifling bureaucracy. But most importantly, they failed to refocus its resources adequately to combat the growing threat from Islamist terrorism. The events of 9/11 took the FBI by surprise. There are, inevitably, some holes in Weiner's story. It is not quite a "history of the FBI": its role as a crime-fighting agency is ignored, so readers expecting to find stories about Al Capone will be disappointed. The 1910s, the Thirties and large parts of the Eighties are barely covered and the author admits there is much that remains a mystery even to him. But this should not detract from a truly impressive piece of research that could have been put together only by a journalist of Weiner's stature. Where Weiner excels is in his description of the constant tension in America between civil liberty and national security. It is the balance between these two forces that keeps America relatively safe, but also relatively free. In one of the most interesting passages, he describes the moment when George W Bush tried to force the FBI to conduct illegal operations to further the war on terror. It was the director himself who insisted that the principles of civil liberty were upheld, and threatened to resign if they were not. It is moments like this that remind us of the subtle power of democracy. For all its many and terrible flaws, the FBI - and even the CIA - have never, quite, been outside the law. Enemies: a History of the FBI by Tim Weiner 537pp, Allen Lane t £23 (PLUS £1.25 p&p) Buy now from Telegraph Books (RRP £25)