Project GAMMA; Delta Force’s Black Sheep Sibling

June 14, 2024

I suspect anyone reading this is aware of Delta Force, the US Army’s premier Tier One special operations unit. Since the unit’s creation in 1977, Delta Force has acquired a legendary reputation, serving in conflicts across the globe to the extent that they have caused the term “operator” to pass into the military lexicon to represent an extremely competent and proficient, well, operator.

In fact, Delta’s origins go back further, arguably to 1964 and the Vietnam War, when Project DELTA was created. This was a small elite unit, a mix of American and South Vietnamese Special Forces that were tasked with conducting special reconnaissance missions deep into Viet Cong territory where they would capture or kill high priority targets or else call in conventional military support to destroy major enemy infrastructure or troop concentrations that they had discovered.

And seeing as Project DELTA was commanded by Charles Beckwith, who later founded Delta Force, I think we can conclude that the groundwork was laid for the later unit and its methods and roles in the mid—60’s, with counterterrorism thrown in for good measure.

But Project DELTA wasn’t the only such special taskforce created for long-range recon missions behind enemy lines, and while DELTA operated in Vietnam the wholesale infiltration of neighbouring Cambodia by communist forces meant that another unit was needed to combat that.

Project GAMMA, also designated as Detachment B-57, 5th Special Forces Group.

Naturally, operating in Cambodia was a highly delicate subject. Cambodia was very publicly neutral in the ongoing conflict in Vietnam, a rather desperate attempt by the…well, lets’ call him Head of State, but essentially the King of Cambodia to stay in power and hopefully keep his country out of the war.

Despite the stated policy of neutrality in fact the Cambodian borders were thoroughly saturated with North Vietnamese forces, who used it as a base for attacks into South Vietnam. This presented the USA with a problem. They didn’t want to blatantly violate Cambodian neutrality, well not yet anyway, so they needed covert options to fight the North Vietnamese and Viet Cong presence in Cambodia as well as gathering evidence to pressure the Cambodian government.

Hence, Project GAMMA.

Because of the super-secret requirements and international nature of the operation, this meant that GAMMA was essentially a joint-Central Intelligence Agency (CIA)/US Army affair. Though notionally a part of the 5th Special Forces Group in fact GAMMA appears to have primarily answered to the CIA

The Agency was deeply involved in the conflict in Vietnam, most infamously known today for the Phoenix Program, which saw tens of thousands of suspected communist guerillas in South Vietnam tortured or assassinated. But in Vietnam itself they did at least have to bear in mind that they had to work alongside the US military and other government agencies if they wanted to get things done, and that put a bit of a brake on some of the things they got up to. However, across the borders in Laos and Cambodia, the CIA was calling the shots.

Project GAMMA was essentially a US Special Forces group under the authority of the CIA and that seems to have created the situation that ultimately led to some rather…unfortunate issues. But I’ll get to that.

In June 1967 Project GAMMA was initiated, with the unit deploying to their primary base at Nha Trang and beginning operations in February 1968. It swiftly proved to be excellent.

Working under military covers as officers working in civil affairs or PSYOPS, the Project GAMMA personnel were swiftly running an elaborate and thorough network involving several hundred agents within Cambodia that was providing critical intelligence on North Vietnamese operations in that country. By October of 1968 intelligence officers in General Abrams headquarters command staff were reporting that sixty-five percent of the information on North Vietnamese Army strength and locations in Cambodia was being generated by GAMMA that year. On top of that they were also responsible for providing around seventy-five percent of the same information on the NVA presence within South Vietnam.

This all provided plenty of targeting information for B-52 raids into Cambodia aimed at disrupting the North Vietnamese presence there and their cross-border attacks into South Vietnam; bombing raids that, again, were not acknowledged.

All in all, Project GAMMA and its elite personnel was shaping up as an incredibly useful asset in the black operations that the US military and CIA were conducting in theatre.

Then the problems started.

In early 1969 Project GAMMA’s agents started disappearing. So sudden and dramatic were the reversal in fortunes for the program that it led to one obvious conclusion.

Project GAMMA had been infiltrated by an enemy agent.

Investigations were initiated to attempt to find the traitor in their midst, but these proved inconclusive. And then the GAMMA personnel got what appeared to be a lead. An SF team operating in Cambodia managed to grab some intelligence material from an NVA base, amongst which was a roll of camera film. When this was developed one of the pictures showed a known senior North Vietnamese intelligence officer in conversation with a GAMMA agent, Thai Khac Chuyen.

Chuyen was promptly put under surveillance, but the suspicion was enough that a…harder approach would be taken. The suspected spy was recalled to GAMMA headquarters and disappeared into an interrogation cell. Here he endured ten days of what is described of as “enhanced interrogation” as well as undergoing polygraph testing and being injected with Sodium Pentathol, otherwise known as “truth serum”.

After ten days of this his interrogators were of the opinion that, yes, Chuyen was the spy responsible for the loss of the Project GAMMA informants. But they also seem to have found out that he was also providing information to the South Vietnamese Intelligence Agency!

Chuyen appeared to be not a double agent, but a triple agent.

Now I should point out that the truth of this, or whether Chuyen was actually guilty, is ultimately an unknown, because now things get shadier.

The Green Berets of Project GAMMA asked what action they should take to deal with Chuyen and, because he was a foreign agent and therefore a CIA asset, they asked the Agency.

Here we get to a case of “he says, she says”.

According to some sources, the instructions came back from CIA how Chuyen should be dealt with: “Terminate with extreme prejudice.”

However, the CIA states that they told the Green Berets that dealing with Chuyen was their problem, but that they strongly advised against killing him. Regardless of who is telling the truth on this, the outcome for Chuyen was the same. On the 20 June 1969 he was injected with morphine, taken in a boat out into the South China Sea and shot twice in the head. His body was then wrapped in chains and dumped into the water.

A cover story was concocted that Chuyen had been sent out on a top-secret mission to explain his absence and that would’ve been that; another dirty secret in a very dirty war.

But that wasn’t to be.

Firstly, General Abram’s office in Saigon received a report of the extra judicial killing the next day, allegedly from the CIA. Abrams has gone down in history as a great commander – the M1 tank is named after him, after all – but he apparently had a pathological dislike of paratroopers and especially didn’t like the Special Forces, a common attitude amongst the so-called “Big Army” officers of the time.

Abrams promptly called the commander of the 5th Special Forces Group, Colonel Robert Rheault, who told the Supreme Commander in Vietnam the cover story.

Rheault’s part in the whole affair is also somewhat murky.

He had taken command of the 5th only in May, so how much he knew about the whole affair is still subject to debate. But it is generally thought that he at least knew the truth of the killing, perhaps authorised it himself, and almost certainly deliberately lied to Abrams about it.

So when Chuyen’s handler, one Sergeant Smith, turned up at the CIA office in Nha Trang, begging to be protected from what he apparently described as “a bunch of wild men” in his unit, Abrams went ballistic. Smith’s fears where apparently inspired by the fact that he had not followed correct security procedures when he onboarded Chuyen into GAMMA, and thought he was about to be “disappeared” too.

Rheault was arrested, along with seven other Green Beret members of Project GAMMA and proceedings for a court martial for murder instituted. Naturally such a situation couldn’t be kept quiet, and the press was all over what became dubbed as “the Green Beret Affair”.

The case raised a number of issues, mainly around the ethics of what the accused said was the elimination of an enemy agent, as per their instructions versus what the prosecutions stated was an extra judicial killing.

And in fact, no decision on the right or wrong of the case was never reached. Despite attempts by the US Navy at Abrams request to recover the body, Chuyen was never found, and when both the General himself and the CIA refused to offer testimony at the court martial, the case was wound up and dropped.

But those accused would pay a price. Rheault, who up until that point was considered a shining star in the US officer corps and was destined for high office in the service was relieved of command of the 5th Special Forces Group and subsequently retired from the Army. He would subsequently be a partial inspiration for Colonel Kurtz in Frances Coppola’s film “Apocalypse Now”.

Project GAMMA itself was shut down in early 1970 and the whole thing brushed away, as much as was possible. But that wasn’t really viable, and a number of questions remained unanswered that continue to be subject for historical debate today.

Just what was Thai Khac Chuyen’s role? Was he a double agent, or was he a South Vietnamese asset? Indeed, was he simply playing everyone off against each other?

It seems that this particular question will never be answered, nor just who was calling the shots on the decision to kill him.

While the CIA were quick to blow the whistle on the affair, their remains a strong sentiment, especially amongst the Special Forces community, that they made the call all along and that Colonel Rheault and his men were simply scapegoats sacrificed to protect the Agency.

Again, with the CIA and the US Army having drawn a very definite line under the whole affair, with Project GAMMA being excised even from official histories, it seems we shall never know. But the reverberations of the case continue to sound today, especially after the War on Terror, which threw up its own share of ethical questions on what is permissible in conflicts.

Plus, Project GAMMA and the Green Beret Affair did play a part in ending the Vietnam War, though not to the result originally intended by the program, and indeed had a wider impact than recognised.

While the press was in a frenzy covering the court martial one Daniel Ellsberg, a military analyst with the RAND Corporation, was busy making copies of a damning secret study that spelled out how multiple administrations had lied to the American people and Congress about the actual policies being implemented for the war in South East Asia. These, referred to as “The Pentagon Papers”, both further eroded the declining support for the war in the United States when published in 1971 but also reinforced the power of the press and the role they can play in holding those in power to account.

When the New York Times was forbidden from publishing any further material from the report by the Nixon Administration the Supreme Court found in newspaper’s favour, reinforcing the importance of the First Amendment of the US Constitution and highlighting the importance of “an informed and critical public opinion which alone can here protect the values of democratic government.”

And one of the critical elements in persuading Ellsberg to make his copies of the report that would create such a bombshell were the stories in the press about the killing of Chuyen. Ellsberg, a former US Marine officer, was outraged by what he saw as the blatant violation of the Laws of War by US soldiers and a disgrace, as he later put it,  to “military honor”.

*Ellsberg marine

So, while Project GAMMA may not have ultimately gone on to achieve the military glories of its DELTA sibling, it seems that it had an important, and often unremembered, impact after all.


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