WASHINGTON -- John H. Sununu is not the first White House chief of staff to be a political lightning rod.
Recent political history suggests that the more personal power the chief of staff accrues, the more exposed -- and expendable -- he becomes.
Ever since President Dwight D. Eisenhower introduced the military rank to the White House, the position's importance has grown in direct proportion to the size of the executive branch and the complexity of the president's business.
"As the White House has become larger, it needs a handler. It needs somebody to allow the president to do the things that are important. In many ways, the chief of staff is the president's chief gatekeeper," said Stephen Hess, author of "Organizing the Presidency," who became consultant on executive office operations to President Jimmy Carter in the 1970s and is now senior fellow in governmental studies at the liberal Brookings Institution.
Mr. Sununu's departure, according to Mr. Hess, should surprise no one. He was brought into the White House to play the "bad guy," and did it effectively.
"It's hard to make friends in that role," Mr. Hess said. "He lasted three years. He might have lasted longer except the economy turned sour and everybody started to point their finger at the next guy."
Hale Champion, who served two terms as chief of staff to California Gov. Pat Brown in the 1960s, compared Mr. Sununu's style of running the Bush White House to the way the Reagan administration was controlled by Donald T. Regan, the most recent precedent for a powerful chief of staff running out of string.
Mr. Regan left after first lady Nancy Reagan decided he had become too powerful for his own and her husband's good. The aggressive Mr. Regan was replaced by the more diplomatic former senator from Tennessee, Howard H. Baker Jr.
Mr. Sununu's undoing, according to Mr. Champion, who is now with Harvard University's Kennedy School of Government, was the power over domestic policy that Mr. Bush had ceded to him.
"Sununu has been running a good part of the domestic program for the president. He has had it delegated to him by Bush. He has let Sununu look after everything from the budget summit of a year or so ago to dealing with Congress on issues like health," said Mr. Champion.
"Sununu," he added, "is seen by many people as a political decision-maker on his own. When something like the economy comes along, where he has been a major player and he is seen as not handling it very well, a lot of people who want to defend the president say, 'John Sununu was doing that.'
"If life were sweet in the White House and there were no problems, and Bush was still at 90 percent popularity, and all was well with the world at home and abroad, then nobody would care about the chief of staff. But when there starts to be trouble, and when it's either the president or somebody else, you start looking for somebody else. And the chief of staff, if you don't like him anyway, is No. 1 on the list."
Other powerful chiefs of staff have come to grief. One of them, like Mr. Sununu, was a former governor of New Hampshire -- Sherman Adams. As President Eisenhower's chief of staff, Mr. Adams condemned conflicts of interest while accepting a payoff from an industrialist on whose behalf he interceded with the Federal Trade Commission.
Corruption Watergate-style was behind the downfall of another tough chief of staff, Bob Haldeman, whose efforts to protect President M. Richard Nixon ended in his departure from the White House.