In his new book One Man Against the World, Tim Weiner explores some of the questions surrounding the presidency of Richard Nixon, pictured above in the Oval Office on Feb. 19, 1970.
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J. Edgar Hoover was the first director of the FBI. He introduced fingerprinting and forensic techniques to the crime-fighting agency, and pushed for stronger federal laws to punish criminals who strayed across state lines. He also kept secret files on more than 20,000 Americans he deemed "subversive."
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