After graduating university, Zion worked as a trial lawyer until becoming Assistant US Attorney for
New Jersey in 1961. He then turned to journalism and writing novels. He worked for various New York publications, including
The New York Times,
New York Daily News,
New York Post and
New York Magazine. In 1971, Zion revealed that
Daniel Ellsberg was the source of the
Pentagon Papers, the classified study on the history of
United States' political and military involvement in Vietnam from 1945 to 1967. It detailed the
Johnson Administration's deceit in Vietnam, and at that time was being published by the
Times and
The Washington Post. Zion, who was not affiliated with any news organization at the time, made the revelation on a popular New York City radio show. He owned a steakhouse during the early 1980s called
Broadway Joe. It was located on West 46th Street. == Personal life ==