Snip:
The morning press briefing, which is held between nine-thirty and ten, is called “the gaggle”; it’s less formal, and TV cameras are banned. Before September 11, 2001, the gaggle was held in the press secretary’s office, with a dozen or so reporters crowded around his desk. These days, the forty-eight press seats in the James S. Brady Press Briefing Room are often filled, and, when McClellan arrives, the podium is already crowded with tape recorders.
The press and the press secretary have come to use the gaggle as a dry run for the televised briefing, at about twelve-thirty. McClellan says, “I get a sense of what they’re thinking.” Ari Fleischer, whose briefings were often more vituperative than McClellan’s, recalls that each morning he felt both the rush of “stimulation” from the pending contest and like “a piñata” as he was pummelled by reporters. Since Herbert Hoover appointed the first press secretary, in 1929, the role has changed—often depending upon the relationship between the press secretary and the President, as well as on the condition of the Presidency. Pierre Salinger, who worked for J.F.K., was in many ways superfluous; Kennedy was essentially his own press secretary. Jody Powell, who served Jimmy Carter, was popular because the working press trusted him and knew that he was close to the President. Ronald Ziegler, who worked for Richard Nixon during the Watergate scandal, fell regularly into the piñata category; Clinton’s press secretary Michael McCurry and his successor, Joe Lockhart, rarely did—even during the Lewinsky affair.
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http://newyorker.com/fact/content/?040119fa_fact2