"Enemies - A History of the F.B.I." by Tim Weiner - NYTimes.com On Dec. 31, President Obama signed the National Defense Authorization Act, which allows for the indefinite military detention, without trial, of any American citizen "who was a part of or substantially supported Al Qaeda, the Taliban or associated forces that are engaged in hostilities against the United States or its coalition partners." This act effectively abrogates the Bill of Rights and removes one of the cornerstones of Western liberty. But not to worry. In a signing statement, Obama pledged that he would not authorize any such detentions. What a curious position for a former constitutional scholar to take: the promise of one man substituted for the rule of law. It is just such presidential hubris, Tim Weiner makes clear in his important and disturbing new book, "Enemies: A History of the FBI," that bears much of the blame for the worst violations of our freedoms in this century. Contrary to conventional wisdom and Clint Eastwood movies, J. Edgar Hoover did not accumulate his power by barging into the Oval Office with a thick dossier of dirt on each new president and his family. Hoover was indeed a vicious gossipmonger, yet the most damning information he possessed could not be disseminated easily. No newspaper of his time would print it, no radio or television station would broadcast it. The harder truth is that most presidents since Woodrow Wilson have been less intimidated by the F.B.I. than seduced by it. Under the rubric of protecting the nation, they secretly authorized the F.B.I. to open mail, infiltrate political parties, tap phones, perform "black bag" break-ins of homes and institutions, and draw up vast lists of Americans eligible for "custodial detention" during a crisis. Or at least Hoover said they did. Often, his "authorization" came from an unrecorded, private conversation with the chief executive. When presidents or attorneys general or the Congress tried to rescind these dubious mandates - or when they were explicitly struck down by the highest courts in the land - he usually ignored these authorities. Any power ever granted to the F.B.I. he considered to be his in perpetuity. A classic paranoid, he fostered paranoia everywhere. When the F.B.I. tapped the home phone of a Supreme Court clerk in 1936, Weiner writes, "Chief Justice Charles Evans Hughes suspected that Hoover had wired the conference room where the justices met to decide cases." Yet Weiner also makes clear that the problem went beyond Hoover. The F.B.I., as Robert Penn Warren wrote about the rest of humanity, was "conceived in sin and born in corruption." When Theodore Roosevelt first proposed a national police force in 1908, Congress said no, fearing "a central police or spy system in the federal government." Roosevelt simply used a "special expense fund" at the Justice Department to quietly hire 34 agents for his new "Bureau of Investigation." To this day, the F.B.I. lacks a formal charter, and its financing has often been shrouded in secrecy. This opaqueness, unsurprisingly, has not improved performance. Wiselyconcentrating on the F.B.I."s secret intelligence operations, Weiner lays bare a record of embarrassing, even stunning failure, in which the bureau's lawlessness was matched only by its incompetence. The F.B.I. conducted huge raids against pacifists, labor leaders and other dissidents during World War I, directing the arrest of tens of thousands of individuals. Yet it failed to uncover a single enemy spy, even as a nest of them blew up the enormous Black Tom munitions dump in Jersey City, riddling the Statue of Liberty with shrapnel. Combating Nazi agents before and during World War II, the F.B.I. was, by its own assessment, "a laughingstock." During the cold war, a Soviet spy said its agents were "like children lost in the woods." The bureau often seemed as alarmed by its new rival, the C.I.A., as it was by foreign intelligence networks. It failed repeatedly to break up spy rings like the Rosenbergs," even forgetting it already had damning evidence in its files against the atomic spies Harry Gold and Klaus Fuchs. Hoover himself derided the "gross incompetency" of his agency in failing to keep better tabs on Lee Harvey Oswald after his return from the Soviet Union. Kevin Baker is a novelist and historian who lives in New York City.