If you stare too hard into the shadows, sometimes you don't see what is really there, only what you imagine ought to be there.

This was the case last week when Time magazine and Cable News Network's "Newsstand" asserted that in September 1970, U.S. Special Forces used sarin, a lethal nerve gas, on a Laotian village believed to be harboring American soldiers who had defected.These reports are untrue. Along with about two dozen other Green Berets, I was on the helipad when our Special Forces team, code-named the Studies and Observations Group, returned from the covert mission in question, known as Operation Tailwind.

As the soldiers on the mission discussed what they had done, not one mentioned nerve gas. Nor did anyone mention having seen, much less killed, American deserters. Had American defectors - or, for that matter, any Caucasians - been seen at such a site, and had any poisonous gas been used, we would have talked about little else, so astonishing would those occurrences have been.

What of the "village" CNN and Time claim was wiped out? It was, in fact, a "Binh Tram," a logistical sub-headquarters on the Ho Chi Minh Trail. Its inhabitants were not women, children or American deserters, but North Vietnamese soldiers.

How could Time and CNN have gotten it so wrong? They mixed up two different gases. On Feb. 2, 1968, the Joint Chiefs of Staff authorized the use of CBU-19, a tear gas, for search-and-rescue operations in Laos. Even the use of tear gas was politically sensitive then, according to the U.S. Air Force's authoritative history, "Search and Rescue in Southeast Asia," published in 1992.

Gen. Creighton Abrams, the commander of all forces in South Vietnam, had to approve any use of tear gas by Special Forces in covert operations. Indeed, using tear gas was so delicate a matter that it normally meant a delay of perhaps an hour or two while we waited for clearance and then loaded the special tear-gas bombs aboard helicopters at Nakhon Phanom, Thai-land or Danang, South Vietnam. There was further delay if we had to wait for gas masks.

While writing a book on the Special Forces in Vietnam, published last year, I tracked down rumors that a "sleeping gas" of some kind had been used on these missions. All my sleuthing led to a single answer: The agent was CBU-19.

The leading expert on the Studies and Observation Group in South-east Asia, Richard Shultz, a professor at the Fletcher School of Law and Diplomacy at Tufts University, has spent two years investigating the topic. He has had access to all available documents, classified and unclassified, and has interviewed every significant military and CIA official involved with the Special Forces. And he too concludes that the Special Forces never used nerve gas.

A few months ago, when CNN was preparing its report, a number of veterans alerted April Oliver, the CNN producer, that the allegations about nerve gas could not possibly be correct. But the program, when it was broadcast, played down our testimony.

Instead, CNN advanced the claims of one man, Lt. Robert Van Buskirk. His claims are especially astonishing since his own book about the mission, "Tailwind," published in 1983, does not mention nerve gas or American defectors.

The person who knows the most about Operation Tailwind, Col. John Sadler, the commander of America's covert operations in Southeast Asia in 1970, declined to be interviewed by CNN. But he has unequivocally rejected Van Buskirk's version of events.

"I did not order this," he told me after CNN's broadcast, "and I would have had to know if this had happened."

As for Van Buskirk's claim that the raid was intended to kill American defectors, "This is simply not correct," Sadler told me. "Operation Tailwind was a diversion to draw North Vietnamese forces away so an allied attack could succeed in southern Laos. It was a clear-cut mission, and I should know because I ordered that operation."

Capt. Eugene McCarley, who led the Tailwind commandos, has also said the CNN report is inaccurate. I spoke with him too after the telecast.

"American deserters were never mentioned in our mission briefing," he said. "We never saw a single Caucasian during the operation. There were no defectors there. Looking for defectors was not our mission."

He added that no lethal chemical agent of any kind was used during the operation. When he was interviewed by CNN, McCarley rebutted Van Buskirk's accusation. But instead of broadcasting his forceful words, the producers paraphrased and minimized them.

Van Buskirk's claims are also highly implausible on technical grounds. For instance, the gas masks used in Vietnam didn't offer effective protection against nerve agents, which can penetrate ordinary clothing. These masks, however, did protect troops from tear gas.

Army guidelines required soldiers to wear full chemical protective suits when they were in areas exposed to nerve gas. No such suits were ever issued to us in covert operations, and I doubt that any were ever used in Vietnam.

According to Van Buskirk, nerve gas had been dumped on the "village" the night before he and his team, without gas masks, attacked it. Yet Army guidelines require waiting 32 days before sending unmasked troops into an area struck by sarin.

Other essential equipment was missing as well. "We did not have a single atroprine injector," McCarley told me, referring to a common antidote for sarin. "If nerve gas actually had been present, we would absolutely have needed atropine."

Nor were his men issued field decontamination kits, small plastic containers that include the special powder needed to counteract the poison. What is more, when the team returned, the soldiers did not go through the lengthy, complex decontamination procedures required after exposure to nerve gas.

Indeed, everyone, including me, went straight to the club for a drink!

In its report, CNN said that Adm. Thomas Moorer, the former chairman of the Joint Chiefs, confirmed the use of sarin. But CNN, which said his confirmation came "off camera," quoted snippets that didn't add up to a direct confirmation.

Perhaps CNN's greatest shortcoming was its failure to offer one reason for the military to have used nerve gas - especially since the potential political consequences would be so high. Why use nerve gas four months after the Kent State killings, during the height of the anti-war movement? Wouldn't the North Vietnamese have gone out of their way to protest and publicize so horrendous a war crime?

Tragically, CNN and Time magazine missed the real story - the great sacrifice and courage of the troops in Special Forces who risked their lives, secretly, against tremendous odds and with no recognition from a nation that showed no gratitude at the time. If CNN and Time are any measure, there seems little gratitude today, either.