Tonight we're going to present evidence of what we have come to believe was a conscious effort -- indeed a conspiracy at the highest levels of American military intelligence -- to suppress and alter critical intelligence on the enemy in the year leading up to the Tet offensive. -- "The Uncounted Enemy: a Vietnam Deception," CBS documentary, Jan. 23, 1982

Starched and confident as he stood in a Pentagon briefing room 17 years ago, Gen. William C. Westmoreland showed no visible reservations when he said that peace in South Vietnam "lies within our grasp."

"The enemy's hopes are bankrupt," the commander of U.S. forces in Vietnam assured reporters and their audience of Americans, many troubled and divided by this distant war.

Fifteen years later, in a 90-minute television documentary called "The Uncounted Enemy: a Vietnam Deception," CBS charged that Westmoreland and other high government officials were conspiring at the time to keep the enemy's actual strength a secret not only from the press and public, but also from the president.

It could be argued, CBS said, that such rosy predictions about the war left Westmoreland's commander in chief, President Lyndon B. Johnson, unprepared for the Tet offensive in January 1968 when the enemy waged a massive guerrilla attack in spite of Westmoreland's rosy predictions that their numbers were waning. Such a tactical blunder, according to CBS, helped lose the larger war for public support.

Now CBS and Westmoreland will defend their versions of this pivotal time in the Vietnam war in a trial expected to become one of the most important and perhaps bitter courtroom dramas of this decade.

It is a battle for reputations, in one sense, as Westmoreland's attorneys accuse the network of bad journalism and CBS lawyers charge that Westmoreland hid the truth about the unpopular war.

But the trial of Westmoreland's $120 million libel suit against CBS, scheduled to start Tuesday in U.S. District Court in New York, is more than the latest skirmish between titans from the media and the military. Some of those observing say the trial could be the first major and official inquiry into this crucial period of the war.

Years and miles from the conflict, scholars for the military and the press also hope for new answers, or at least new perspectives, about whether the war was lost on the battlefield, in the war rooms or during the nightly news.

And, as the inner workings of a major network are revealed, some other issues also could emerge that have become emotional in a society increasingly critical of its press establishment.

For example, can a public official sue successfully over press criticism of his job? Can a journalist have preconceived beliefs about a story? There also is the even larger question of whether the press has become as arrogant now as some in government and the military seemed to be 20 years ago.

"Among the questions in dispute will be whether the high U.S. military command in Vietnam engaged in willful distortion of intelligence data to substantiate optimistic reports of the progress on the war and whether one of the nation's most important distributors of news and commentary engaged in willful or reckless slander," wrote U.S. District Judge Pierre N. Leval, who will try the case.

As Leval explained last month when he reluctantly turned down a request that the trial be televised, the drama to be played out in his courtroom is destined to be "a rare debate and inquiry on issues of highest national importance."

It also could be a rare opportunity for some of the most reluctant managers of the Vietnam war to go on the record in their testimony about one of the war's most crucial periods: the months before the Tet offensive.

The case will feature some of the big names from the Vietnam era, including television journalism stars. Also important could be some of the usually anonymous military and intelligence people who are expected to tell how they did their wartime jobs.

The lineup of witnesses available for Westmoreland reads like a "Who's Who" of the Johnson administration, including former secretary of defense Robert S. McNamara, former secretary of state Dean Rusk, former CIA directors William E. Colby and Richard Helms, Gen. Phillip B. Davidson, Gen. Joseph A. McChristian and President Johnson's special assistants on national security affairs, McGeorge Bundy and Walt W. Rostow.

By contrast, CBS has as potential witnesses a number of intelligence analysts who worked for the Army and the CIA in Vietnam and Washington as opposed to the policy-makers who are potential witnesses for the other legal team.

As David Halberstam, author of "The Best and the Brightest" and one of CBS' potential witnesses, said: "What you have here is most of the people who were the sources for those of us covering Vietnam. They are the ones testifying for CBS -- the people who actually did what the brass told them."

As the trial nears, it becomes apparent that Westmoreland will try to concentrate on the issue of whether he misled President Johnson, instead of whether he distorted facts to the press, the public and Congress. It also has become clear that the big names have become more important in this trial.

David Boies, the lead attorney for CBS, said at a news conference Friday that the policy-makers from the era will be asked "whether they were part of the deception or part of the deceived."

In many ways, the event that spawned this legal drama was an internal conflict between two arms of the U.S. government: the CIA and the Army. Not uncommonly in the workings of government, both had the same task in late 1967: assessing the strength of the enemy.They came to different solutions. The Army said the range of enemy troop strength was near 300,000 and the CIA suggested it was closer to 600,000. As Professor John P. Roche, former special consultant to Johnson, said in his affidavit, such matters were not easy. "There was an arcane quality about much of it which reminded me of the disputes among 13th-century scholastics: how does one count the guerrilla's child, who once a month goes out to plant punji sticks?"

But for CBS, the question of troop strength will be crucial during the trial because the documentary charged that Westmoreland kept a "ceiling" of 300,000 on any enemy troop assessments by the Army.

In this regard, one of the most crucial witnesses for CBS and the one who could be among the most colorful in the network's lineup is expected to be a slow-talking Republican from West Point, Miss., retired Army Col. Gains Hawkins.

Hawkins said during pretrial testimony that he "reduced figures arbitrarily," that he believes the reductions were part of a "cover-up" and that he blames Westmoreland for ordering a whitewash of the enemy's strength to maintain public support for the war.

George Allen, a 20-year veteran of the CIA who uses the CBS documentary to train agency recruits, said, "I think we were accessories to the conspiracy to mislead the American people."

Richard D. Kovar, a 30-year CIA veteran who now prepares President Reagan's daily foreign intelligence digest, praised former agent Sam Adams, a retired CIA analyst who was a paid consultant for CBS and who has spent virtually the last 15 years building the case that CBS will carry to the court.

"Sam Adams had been right, and I and Mr. Helms . . . had been wrong," Kovar said in his affidavit. "It was not just the CIA versus the Army, but ultimately a matter of truth or consequences, and the consequences had been military and political defeat and death and maiming for untold numbers of Americans and Vietnamese."

Thus, in the strictest sense, the court will try to determine whether Westmoreland and others "cooked the books" in favor of the Army numbers as Mike Wallace, the narrator of the documentary, put it, or whether Army officers simply stood by their own figures against the CIA's because they believed they were more solid.

As Westmoreland's lawyer, Dan Burt, wrote in one argument to the court: " CBS took what was essentially a debate in 1967 over how the enemy should be portrayed . . . and converted the debate into a conspiracy."

Still, the questions before the court will be much larger than a mere discrepancy in the numbers. Ultimately, historians hope to find new evidence of whether underestimating the enemy strength set the nation up for a fall when the Vietnamese suddenly waged the massive Tet offensive two months later.

Westmoreland and his backers will argue that Tet was a big military victory for the United States but a psychological loss because of the way the media covered it and the world perceived it.

As Gen. Maxwell Taylor writes in his autobiography, "Swords and Plowshares," 30,000 of the 84,000 enemy troops committed to Tet were killed in the first two weeks -- "the flower of Ho Chi Minh's" army, as he puts it.

"While the enemy was losing the war on the battlefield, he was gaining a valuable psychological victory in the United States and in large parts of the world," Taylor wrote. "The general public was shocked by the unexpected vitality shown by an enemy whom many had supposed to be on its last legs."

CBS lawyer Boies and his team wrote last May when they were trying to get the case dismissed, "The Tet offensive was a turning point in the war -- not because it was a military victory for the enemy but because the magnitude of the offensive gave lie to Westmoreland's reports of declining enemy strength and began to sap the entire war effort of its credibility and support."

If CBS will be trying to prove that Westmoreland misled not only the public but also his superiors, the other side will be looking at how Wallace and his producer, George Crile, made a broadcast that the general called a "preposterous hoax."

Under the nation's libel laws, Westmoreland and his lawyers, funded primarily by a conservative public law group called the Capitol Legal Foundation, will have to prove that at least Crile and perhaps others at CBS were trying to ruin Westmoreland's reputation by making damaging charges "with reckless disregard whether they were true or false."

The results may well turn out to be embarrassing to CBS and professionally devastating to Crile, who told one reporter that the months in the courtroom would become a "real-life test" for him. Crile was suspended by CBS for secretly taping an off-the-record interview and his job is considered in limbo until the case is over.

Ironically, some of the strongest arguments for Westmoreland's side of the case have been made by CBS itself. After TV Guide wrote an analysis of the program, which it called "Anatomy of a Smear, or How CBS Broke the Rules and 'Got' General Westmoreland," CBS News President Van Gordon Sauter ordered an internal investigation.

Two months later, 25-year veteran CBS producer Burton Benjamin issued an internal report that said Crile and his team had failed to prove a conspiracy and violated CBS guidelines set up after the furor caused 13 years ago by the CBS documentary, "The Selling of the Pentagon."

In pretrial arguments, Westmoreland attorney Burt has accused Crile of leading interviews into areas that built up Crile's case, of cutting short opposing views and of splicing and recasting the film into what Burt describes as "editing fabrications."

Asked Friday at a pretrial news conference how he felt about the show the first time he saw it, Burt said he was convinced by the program. "I said, 'My God, he did it,' " Burt said.

He said he now believes the show is "an enormously powerful work of art" on the order of an impressionist painting or the movie "Patton."

In his statements to the court, Burt has said that "every time there was an opportunity to construe the facts against General Westmoreland, defendants did so."

The statement of Westmoreland's case concentrates on Crile and picks up parts of the CBS internal investigation that quoted Crile's colleages as calling him "obsessive" and "a conspiracy thinker."

Some of the quotes most embarrassing to CBS may well be among tapes provided to Westmoreland's attorneys by Don Kowet, who coauthored the 1982 TV Guide article and recently expanded the story into a controversial book called "A Matter of Honor."

Kowet surrendered to Westmoreland attorneys tapes of telephone conversations with CBS personnel that were originally considered by those interviewed to be "off the record." Among those recordings are comments by the broadcast's executive producer, Howard Stringer, that Westmoreland's reputation was "intact out of all proportion to his failings." A researcher, Carolyne McDaniel, is quoted as saying she believed Westmoreland was a "lousy" general.

If the trial pits the general against the network, it also could open old schisms and be the forum for settling of old grudges.

In looking at more than 250,000 pages of depositions and affidavits from more than 100 witnesses, it is clear that the yeomen will contest the brass, the CIA will compete with the Army and several personal antagonisms could surface.

But, much as elsewhere in the avalanche of documents about the case, there occasionally emerge some of the bitter frictions that divided the government during the Vietnam conflict the way they divided the nation's populace.

Kovar, for example, blames Lt. Gen. Daniel O. Graham, adding in his affidavit that he was "an upward-climbing careerist who let nothing and nobody stand in the way of his grandstanding efforts to win the favorable attention of his superiors."

Graham, who was Westmoreland's chief of estimates, was confronted by similar charges during the CBS broadcast.

"I never blocked any information going forward," Graham told interviewer Wallace. "I'm not that dumb."

In the final round, of course, such differences will be merely fascinating sideshows. At center could be the unanswered question in an exchange between Westmoreland and Wallace in the CBS documentary:

Wallace: "Shouldn't someone from Westmoreland's command have told the president that not only were the VC Vietcong planning a massive attack but that they were flooding the South with North Vietnamese regulars?"

Westmoreland: "We, sure. That was known, that was known."

Wallace: "The president knew?"

Westmoreland: "I have no idea whether the president knew or not.