THE BBC's FIVE-PART "Watergate" is not only the best documentary since "The Civil War," it's also something every American should watch.

A retelling of the events before, during and after the Watergate break-in - a "second-rate burglary" that brought down a president - this five-hour documentary is more riveting than any fictional political thriller. "Watergate" details the lessons that Richard Nixon was forced to learn - and that the American public is all too quickly forgetting."As far as the lessons of Watergate, I don't think there have been any," said John Dean, Nixon's White House counsel and the man whose testimony led directly to Nixon's resignation. "We seem to be a nation that does not particularly like to learn from our history."

Indeed, it took the British Broadcasting Corp. to put together this definitive documentary. "I think the BBC is able to get people to talk who otherwise would be reluctant," said producer Brian Lapping in a recent appearance.

As a matter of fact, the BBC team conducted interviews with nearly all the Watergate principles except Nixon himself. The 55 interviews included everyone from the conspirators - Dean, John Ehrlich-man, H.R. Haldeman (in the last interview before his death), Jeb Magruder - the burglars (including G. Gordon Liddy), the prosecutors (including Archibald Cox), a member of the grand jury that wanted to indict Nixon, even Nixon's second vice president, Gerald Ford - an amazing array.

(And Nixon - who resigned from office 20 years ago this Tuesday - appears via news footage of the period and David Frost's famous 1977 interviews, including outtakes from those interviews that have never been seen before.)

"Probably the single most important thing that made people agree to see us was that we were from the BBC, that we were objective," said producer Norma Percy. Indeed, the producers admit that when they began work on the documentary they were unconvinced that the prevailing view - that Nixon was indeed guilty of the crimes that forced his resignation - was factual.

"When we began we were not by any means committed to the view that John Dean's version of this story was correct," Lapping said. "Indeed we were committed to a somewhat opposite view."

But the evidence piled up that Nixon was indeed guilty. The documentary dispassionately lays out that evidence - most notably tape recordings of Nixon himself authorizing the cover-up - leaving no doubt as to the former president's culpability.

"Like many national traumas, Watergate is starting to become a fertile field for the revisionists," Dean said. "And the stuff they're putting out - it's absurd."The five one-hour segments of "Watergate" follow this amazing tale from before the break-in at Democratic National Headquarters to Nixon's resignation. Part 1 looks at the events leading up to the burglary; Part 2 deals with the plotting of the cover-up; Part 3 how the cover-up fell apart; Part 4 Nixon's battles to prevent the release of the damning tapes to the prosecutors and Congress; and Part 5 the events that led to his resignation.

What helped convince the producers was also what convinced the prosecutors that Dean was telling the truth. Part 3 of the documentary recounts the moment when the prosecutors informed Dean that the Oval Office tapes existed. Dean immediately broke into a big smile, knowing that corroboration for his testimony existed.

In the course of their investigation, the producers found a "smoking gun" memo in White House chief of staff H.R. Haldeman's files - a memo in which Haldeman authorized the Watergate break-in.

And when the producers showed the memo to Dean, "He picked up the document and said, `You found it!' " Percy said. "Which really convinced us that we had found something."

(The memo does not, however, prove that Nixon knew of the break-in before it happened, although several key figures - including Dean - maintain that if Haldeman knew, Nixon knew.)

The documentary also includes previously unheard Oval Office tapes and Haldeman talking about his diaries of what was happening in the White House - as well as his "home movies" of Nixon and other key Watergate figures.

The documentary offers some insight into not only what Nixon did but why he did it. But that's a question that can never be fully answered.

"He's the strangest man I've ever met," said Dean, who admitted that as a 30-year-old attorney, he was in "awe" of Nixon.

"But every time I dealt with him there seemed to be a very mean streak I found I was dealing with. . . . This is a man who for some reason needed to control his entire world. Much of the so-called political intelligence that was gathered was really an effort by Nixon to know, one, what his opponents or enemies were up to; but, two, to give him information, hopefully of a negative character, that somehow would enable him to have some control over those he thought of as his opponents."

The American version of "Watergate" is narrated by Daniel Schorr, who covered the scandal for CBS News and was on the infamous Nixon Enemies List. (See accompanying story.) And Schorr praised the documentary not only for its accuracy, but for reminding people that Watergate was "an organized attempt to subvert the American Constitution."

"Had it not been that the president bugged himself and destroyed himself, we might have seen an almost dictatorial takeover of the Constitution of the United States," Schorr said. "Every year at the Passover Seder it is always said, `And this must be told to generation after generation so that they will know about what happened.'

"Watergate has to be told to every generation of Americans. We came close to losing democratic control of the government then."

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ADDITIONAL INFORMATION

`Watergate' on Discovery

The schedule for the five-part documentary "Watergate" on cable's Discovery Channel is as follows:

Sunday: Part 1 (10 p.m. and 1 a.m.), Part 2 (11 p.m. and 2 a.m.)

Monday: Part 3 (11 p.m. and 2 a.m.)

Tuesday: Part 4 (11 p.m. and 2 a.m.)

Wednesday: Part 5 (11 p.m. and 2 a.m.)

Sunday, Aug. 14: Parts 1-5 (2 p.m.-7 p.m.)