The resignation of Richard M. Nixon on the eve of his impeachment in 1974 and the impeachment of Bill Clinton by the House of Representatives and his acquittal by the Senate in the winter of 1998-99 frame three decades of Presidential scandals and scandalmongering in the United States. In "Shadow: Five Presidents and the Legacy of Watergate," Bob Woodward examines the way that the Presidents who succeeded Nixon have struggled to defend themselves in a Washington where the rules of politics and journalism were transformed by Watergate.

Woodward, who with his fellow Washington Post reporter Carl Bernstein helped to expose Nixon's criminal wrongdoing, is one of the celebrated journalists who changed the rules. In "Shadow," Woodward, now an assistant managing editor for the newspaper, has written what is in effect two books. The first re-examines crises of Administrations from Gerald Ford's to George Bush's, including allegations of a deal by which Ford pardoned Nixon, the Bert Lance affair during the Carter Administration, the Iran-contra scandal during Ronald Reagan's Presidency and the investigation of George Bush and his aides by the Iran-contra independent counsel. The second is an account of the Clinton White House's efforts to manage the series of scandals from Whitewater to Monica Lewinsky.

The book-within-a-book about the Clinton White House has attracted the most attention. Woodward's trademark brand of investigative journalism, which has produced "All the President's Men," "The Brethren," "Veil," "The Commanders" and "The Agenda," among other best sellers, is characterized by an often criticized reliance on unnamed sources (whose ranks include the most famous of all, Watergate's "Deep Throat"). In "Shadow," Woodward names his sources in his sections on Presidents from Ford to Bush (Carter and Ford agreed to be interviewed; Bush declined). For most of his information about the Clinton Administration, he cites "knowledgeable sources."

This is not as troubling as it might be, for the simple reason that it is fairly clear who most of Woodward's informants are. The story of Bill and Hillary Clinton's efforts at scandal containment is told almost exclusively from the point of view of the White House legal team and press aides. In great detail Woodward reconstructs one-on-one meetings between Clinton and his lawyer Bob Bennett and between the First Lady and the White House press secretary Mike McCurry. He also reports the details of a private conversation between Hillary Clinton and Jane Sherburne, a White House aide.

No man is a hero to his valet -- nor, it appears, to his lawyers and press secretaries. The portraits of the Clintons by their deputies are not flattering: Woodward's Bill Clinton lies, rages and sulks, while Hillary Clinton is given to sobbing when she is not ordering aides to stonewall. By contrast, most of Woodward's presumed informants are shown in a flattering light. A number of distinguished Washington lawyers, including Lloyd Cutler and Abner Mikva, who became White House counsels, and Bob Bennett, who headed Clinton's legal team in the Paula Jones case, warn the President to be forthright, only to be disillusioned when he refuses to confide in them. In a reversal of a cliche of Washington drama, a series of insiders grows disenchanted with the cynicism of a younger politician from the hinterland. Here is a typical passage:

"On Friday, Jan. 16, Bennett trudged rapidly up the White House driveway. These two days were going to be the most important in his three decades of practicing law. He was on edge. Am I really going to say this to the President of the United States? he asked himself. He rarely shied away from blunt exchanges with clients. In truth he relished forcing his clients out of their corners of untruth. But he worried that a direct confrontation with the President might be stepping over the invisible line separating ordinary mortals from -- what might they be called -- figures of real history?"

Like Clinton, Kenneth Starr -- to whom Woodward devotes far less attention -- is viewed from the perspective of his aides. One is Brett Kavanaugh, who "looked somewhat like a dark-haired version of the movie actor William Hurt, and he had a similar soft style." Woodward informs us that "Kavanaugh was concerned that Starr thought it was the catalogue of Clinton's sexual behavior that provided a basis for recommending that Clinton should be bounced out of office, rather than the alleged crimes." When Starr decides to indict Julie Hiatt Steele for testifying falsely in the Kathleen Willey case, "Brett Kavanaugh was appalled. . . . An indictment of Steele, Kavanaugh wrote in a memo to Starr, would win the 'trifecta' for abuse of the independent counsel law."

In history according to the underlings, Clinton and Starr are tragic heroes, each with a characteristic flaw -- Clinton's dishonesty, Starr's zealotry. Each marches toward disaster through the pages of Woodward's book, ignoring the prudent counsel of his personal Greek chorus of lawyers.

Some of Woodward's judgments are shrewd and plausible. Dismissing the claim that Clinton's bombing of Iraq the day before debate on impeachment was a diversionary "Wag the Dog" war, Woodward suggests that "the Lewinsky scandal had sufficiently weakened Clinton so that the advocates for the strike had their way." Revisiting the scandals of earlier Administrations, Woodward puts together some interesting details. Here is Ronald Reagan on the arms-for-hostages deal with Iran: " 'As far as I'm concerned, we were right,' the President insisted, glaring at Shultz. 'We were successful, and only press activity has thrown it off.' "

But Woodward's attempt to explain the post-Watergate culture of scandal is perfunctory and unconvincing. "I never expected another impeachment investigation of a President in my lifetime, let alone an actual impeachment and a Senate trial," he writes. "Nixon's successors, I thought, would recognize the price of scandal and learn the two fundamental lessons of Watergate. First, if there is questionable activity, release the facts, whatever they are, as early and completely as possible. Second, do not allow outside inquiries, whether conducted by prosecutors, Congressmen or reporters, to harden into a permanent state of suspicion and warfare."

Woodward criticizes Jimmy Carter for pressuring him and Ben Bradlee, then executive editor of The Washington Post, in February 1977, on the eve of Secretary of State Cyrus R. Vance's trip to the Mideast, to suppress a story about C.I.A. bribes over many years to King Hussein of Jordan. "Carter was angry at the way Bradlee and I had handled the story, which in Carter's opinion pulled no punches and was treated with a banner headline and the full flavor of illicit behavior uncovered. From Carter's point of view, the publication on the day of Vance's arrival in Jordan was totally unnecessary, sticking a needle in the Administration's eye." Woodward continues: "I had a sickening sense of foreboding, of here-we-go-again with another President. I had seen firsthand that Carter had not been straight at all." Can it really be a "lesson of Watergate" that Presidents must condone the publication of sensitive information about covert operations?

Rather than consider the possibility that Presidents might have good reasons to preserve a zone of official discretion and personal privacy, Woodward psychologizes. Presidents since Nixon have been entranced by "the myth of the big-time President," he writes. "But the post-Watergate conditions have made the emergence of such a leader increasingly unlikely, and the Presidents, in frustration, have been in rebellion." Treating these conditions as facts to which Presidents must now adapt spares him the task of raising questions about the role of journalists. Nevertheless, many readers of "Shadow" will wonder whether the problem is not just the imperial Presidency but an imperial press. If the White House forms one vertex of a triangle, the other two corners are made up of news outlets and enemies of the President, from Congressional partisans to White House malcontents.

By focusing exclusively on Presidents' fumbling responses to attacks rather than on the identities and motives of their attackers, Woodward leaves out two-thirds of the story. But to be more comprehensive, Woodward would have had to admit that journalists are players, not merely spectators, in the game of scandal. Despite their disagreements on other matters, the five Presidents Woodward discusses probably would agree with a sentiment he attributes to Clinton in an anguished conversation with his adviser Dick Morris: "They want their own President they can hang."