The Green Beret Affair:

A Tarnished Chapter in Special Forces History

Strategy Central

By Practitioners, For Practitioners

Introduction

In the summer of 1969, a scandal erupted that would forever tarnish the reputation of the United States Army Special Forces, known colloquially as the Green Berets. This episode, which became known as the "Green Beret Affair," centered on Colonel Robert B. Rheault and his involvement in Project GAMMA, a covert intelligence operation in Vietnam. The affair highlighted the murky and often morally ambiguous nature of the Vietnam War, where lines between right and wrong, ally and enemy, became increasingly blurred.

Jeff Stein, the author of the definitive account of the Green Beret Affair, “A Murder in Wartime: The Untold Spy Story that Changed the Course of the Vietnam War” (St. Martin’s Press 1992), kindly reached out to correct elements of this article. He is a longtime journalist and current Editor-in-Chief of www.spytalk.co. He is also a humble and generous man; I recommend anyone more interested in this topic read his book or reach out to him directly.

 Project GAMMA: The Genesis of a Controversy

Project GAMMA, officially known as Detachment B-57, Company E (Special Operations), 5th Special Forces Group (Airborne), was established in 1967 during the height of the Vietnam War. Its mission was clear: to conduct covert intelligence operations in Cambodia, a neutral country that had become a haven for Viet Cong and North Vietnamese forces. Under the command of Colonel Rheault, the detachment excelled in its mission, providing critical intelligence that led to the destruction of enemy operations in Cambodia.

The teams involved in Project GAMMA were comprised of highly skilled operatives, many of whom had extensive experience in unconventional warfare. They operated in the shadows, often in collaboration with the Central Intelligence Agency (CIA), and were tasked with locating and neutralizing Viet Cong sanctuaries across the Cambodian border. The intelligence gathered by Project GAMMA was invaluable to the U.S. war effort, and the detachment's successes earned them a formidable reputation.

However, the success of Project GAMMA came at a high price. The nature of the mission required close collaboration with South Vietnamese forces, some of whom were not always reliable or trustworthy. As the war dragged on, reports began to surface of assets disappearing or being compromised. It was during this time that Colonel Rheault and his team identified a South Vietnamese officer as the likely mole within their ranks.

 A Decision Made in the Shadows

The identification of the South Vietnamese officer as a double agent presented Colonel Rheault with a difficult dilemma. South Vietnamese officer "Thai Khac Chuyen," was suspected of passing information to the enemy, leading to the deaths of American and South Vietnamese operatives. No evidence was ever produced that proved Chuyen passing information to the North Vietnamese other than a photo that was inconclusive at best. Colonel Rhaeault had weak evidence and physical control of a suspect.

Rheault and his team faced a grim choice. Conventional military justice was not an option; the risk of exposing Project GAMMA and its covert operations was too great. Furthermore, the evidence against the suspected mole was circumstantial and unlikely to hold up in a traditional court-martial. The CIA, which had a vested interest in the success of Project GAMMA, allegedly advised Rheault and his team to take extrajudicial action to eliminate the threat.

On June 20, 1969, the South Vietnamese officer was lured to a meeting under false pretenses. He was captured, interrogated, and allegedly executed by the Green Berets. His body was then dumped into the South China Sea, and the operation was quietly buried. For a time, it seemed as though the affair would remain hidden, another dark secret of the Vietnam War.

 The Unraveling of the Cover-Up

However, the secrecy surrounding the execution was not to last. In July 1969, Chuyen's widow went to the US Embassy in Saigon and explained that she suspected her husband had been murdered by the Green Berets who worked with him. Her complaint went up the chain of command to Gen. Creighton Abrams. The General discussed the issue with Colonel  Rhaeault, but recieved an unsatisfactory explanation about Chuyen's disappearance. The General ordered the U.S. Army's Criminal Investigation Division (CID), to launch an investigation into the disappearance of Chuyen. The investigation quickly gathered momentum, and within weeks, seven officers and one non-commissioned officer from Project GAMMA, including Colonel Rheault, were arrested and charged with murder and conspiracy to commit murder.

The arrests sent shockwaves through the U.S. military and the intelligence community. Colonel Rheault, a highly respected officer with a distinguished record, found himself at the center of a scandal that threatened to undermine the credibility of the entire Special Forces. The affair also raised uncomfortable questions about the role of the CIA in Vietnam and the extent to which it was willing to condone extrajudicial killings in the name of national security.

As the trial date approached, the defendants faced the grim prospect of lengthy prison sentences if convicted. The prosecution's case hinged on the testimony of witnesses and the ability to prove that the South Vietnamese officer had been murdered in cold blood. However, the trial took an unexpected turn when the CIA refused to provide key witnesses or documents, citing national security concerns.

The agency's refusal to cooperate effectively crippled the prosecution's case. Without the testimony of CIA officers who had advised Rheault and his team, the government's ability to prove its case was severely compromised. On September 29, 1969, the charges against Colonel Rheault and the other defendants were dropped, and they were released from custody.

 Aftermath and Legacy

The dismissal of charges brought no closure to the Green Beret Affair. Colonel Rheault's military career was effectively over, and the incident stained the Special Forces' reputation. For many within the military and the intelligence community, the affair was a bitter reminder of the ethical and moral compromises, mostly by senior officers, that had become all too common in the Vietnam War.

In the years that followed, the Green Beret Affair became the subject of numerous books, articles, and documentaries. The incident was emblematic of the larger challenges faced by the U.S. military in Vietnam, where the complexities of the conflict often forced commanders to make impossible choices. The affair also reveals how the lines between combat and covert action could become dangerously blurred at the intersection of military operations and intelligence work.

For Colonel Rheault, the affair marked the end of a distinguished career. After his release, he retired from the Army, never publicly speaking in detail about the events that had led to his downfall. In the eyes of many, he was a scapegoat, a man who had been forced to make a difficult decision in the fog of war and had paid the price for it. Others, however, viewed him as a symbol of the excesses and failures of the U.S. military in Vietnam.

The character of Colonel Kurtz in Francis Ford Coppola's 1979 film Apocalypse Now is often cited as being loosely inspired by the real-life figure of Colonel Robert B. Rheault. Like Rheault, Kurtz is portrayed as a once-respected officer who descends into moral ambiguity and operates outside the bounds of traditional military conduct. While Rheault's actions were rooted in the shadowy world of covert intelligence operations, Kurtz's narrative is an exaggerated and symbolic representation of the broader ethical and psychological turmoil faced by many military leaders during the war. Both figures illustrate the dangerous intersection of power, secrecy, and the moral complexities of unconventional warfare, making Kurtz a fictional embodiment of the darker aspects of the Vietnam conflict that Rheault and others experienced firsthand.

Conclusion

The Green Beret Affair remains a controversial chapter in the history of U.S. Special Forces. It serves as a cautionary tale about the dangers of unchecked power, the moral ambiguities of war, and the limits of military justice. More than fifty years later, the affair still raises difficult questions about accountability, the rule of law, and the ethics of covert warfare.

As the United States continues to engage in complex and often shadowy conflicts around the world, the lessons of the Green Beret Affair remain relevant. The incident serves as a stark reminder of the human cost of war and the difficult choices that must be made in the pursuit of national security. In the end, the legacy of the Green Beret Affair is one of caution—a reminder that in war, as in life, the ends do not always justify the means.

For an in-depth look at this series of events, please read Jeff Stein's “A Murder in Wartime: The Untold Spy Story that Changed the Course of the Vietnam War” (St. Martin’s Press 1992),

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Endnotes

1. David W. Hogan, Raiders or Elite Infantry? The Changing Role of the U.S. Army Rangers from Dieppe to Grenada (Westport, CT: Greenwood Press, 1992), 118-120.

2. Thomas L. Ahern Jr., CIA and the House of Ngo: Covert Action in South Vietnam, 1954-63 (Washington, D.C.: Center for the Study of Intelligence, 2000), 194-196.

3. John L. Plaster, SOG: The Secret Wars of America's Commandos in Vietnam (New York: Simon & Schuster, 1997), 281-283.

4. Richard H. Shultz Jr., The Secret War Against Hanoi: Kennedy's and Johnson's Use of Spies, Saboteurs, and Covert Warriors in North Vietnam (New York: HarperCollins, 1999), 235-237.

5. James D. McLeroy and Gregory W. Sanders, Bait: The Battle of Kham Duc (Lexington, KY: University Press of Kentucky, 2019), 301-303.

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This article explores the Green Beret Affair and the complex ethical and moral dilemmas faced by military personnel involved in covert operations during the Vietnam War. The focus on Colonel Rheault's role highlights the challenges of leadership in such a fraught environment, where decisions made in the heat of battle could have lasting consequences.