The Nixon White House hired a shadowy group called the Plumbers to prevent news leaks. But instead, an illegal break-in by the Plumbers inspired a source nicknamed Deep Throat to help the Washington Post. Three decades later, Deep Throat was identified as FBI No. 2 man Mark Felt. Before that, speculation pointed to a dozen or more people, including Pat Buchanan, Henry Kissinger, President George H.W. Bush, Gerald Ford, Gen. Alexander Haig, Sen. Lowell Weicker, Diane Sawyer and even comedian Ben Stein.
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