“Though it has a king, a government and an army, and can be found on a map, Laos does not really exist. Many of its estimated 2,000,000 people would be astonished to be called Laotians, since they know themselves to be Meo (Hmong) or Black Thai (Tai) or Khalom (unidentifiable ethnicity) tribesmen. It is a land without a railroad, a single paved highway or a newspaper. Its chief cash crop is opium.” "Laos: The Four Phases of Nonexistence", Time magazine, 1962

On May 25, 1964, a squadron of U.S. Air Force (USAF) T-28D ground-attack aircraft with Royal Laos Air Force markings took off from Udon Royal Thai Air Force Base in eastern Thailand and flew east over the churning brown whirlpools of the Mekong river into Laos airspace. The Air America pilots cleared the river banks and found open skies above the cliffs and rice paddies of Khammouane province, then banked north toward the highlands of Xieng Khouang province, the frontlines of the Laos civil war, and ultimately the beginning of the Secret War.
Two years prior, in the summer of 1962, the United States, China, the Soviet Union, and 11 other countries signed the International Agreement on the Neutrality of Laos in Geneva, which prevented any nation from engaging in direct or indirect interference in the internal affairs of Laos, forming military alliances with Laos, or establishing military bases in the fledgling eight-year-old nation-state. The agreement was farcical. The U.S. had been providing military aid to the Royal Laos Army since the mid-1950s, while Marxist Pathet Lao forces received military, financial, and logistical support from North Vietnam, China, and the Soviet Union. The terms of the agreement set the stage for a clandestine war waged with “civilian” air corps, a network of remote airstrips known as “Lima sites”, secret refueling stations, hill-tribe mercenaries trained in guerrilla warfare––CIA black-ops funded in part through collusion in the Golden Triangle opium trade. There could be no detectable U.S. military ground presence; the mission in Laos did not officially exist.
In August of 1964, U.S. Pacific Command in Hawaii initiated Operation Barrel Roll with two primary objectives: provide air support for Vang Pao’s Hmong army in the strategic strongholds of Xieng Khouang and disrupt the Ho Chi Minh Trail supply lines that North Vietnamese forces (PAVN) were using to circumvent the bombed-out no-man’s land that separated North and South Vietnam, known as the demilitarized zone (DMZ). The Ho Chi Minh Trail was a labyrinth of jungle paths and dirt roads developed by Vietnamese, Laotian, and Cambodia resistance fighters during the First Indochine War against France. By the time the Americans arrived, it had evolved into a warren of undetectable paths, shielded almost entirely by jungle canopy, spanning hundreds of miles across the frontiers of Southeast Asia.



On April 11, 1967, B-52 Stratofortress bombers flying out of U-Tapao Royal Thai Airfield southeast of Bangkok dropped the first payloads of cluster bombs on eastern Laos, violating both the Geneva accords and the agreement between the USAF and Royal Thai Navy. It mattered little, the USAF war machine had been unleashed. Wave after wave of B-52s carrying up to 50 two-meter-long, five-hundred pound cluster bombs scraped the Laotian skies at 50,000 feet. Each bomb casing opened in mid-air and released around 150 bomblets or “bombies” that fanned out over an area the size of a football field during descent. Upon impact, each bomblet decimated a radius of up to a 150 meters with shrapnel and ball bearings.
Between 1964 and 1973, cluster bombs rained down upon Laos in a deluge of iron and fire. On average, U.S. planes dropped one bomb every eight minutes for nine years. In November of 1968 alone, U.S. bombing missions over the Ho Chi Minh Trail reached 12,800. In total, 580,000 bombing missions were carried out on Laos and more than two million tons of cluster bombs were deployed on an ostensibly neutral country with a population of less than 3 million people. The covert U.S. air campaign left Laos the most heavily-bombed place on earth.
Those in targeted regions did what humans have done to survive war for millennia––they fled to the forests and hid in caves. All but the most defiant among the villagers of Ban Bouam Long, Ban Nasavang, Ban Namuen, and Ban Faay in Xieng Khouang province left their homes, their crops, and their cattle for the relative safety of Tham Piew cave. In the dark recesses, encased in limestone, they listened for the distant, low rolling thunder of B-52s that foreshadowed the coming storms.

Over the next four years, the refugees undertook the Herculean task of transforming Tham Piew into a village. In the “rooms” extending off the 300-meter-long main corridor of the cave, teams of village carpenters furnished the communal living quarters with bunk beds and a classroom with wooden tables and a chalkboard. A communications center was built, as well as a hospital, where a handful of nurses and doctors provided medical care for wounded soldiers, the elderly, and the few women who gave birth. A fresh water spring flowed beneath the rock floor and the communal kitchen ensured no one went hungry. Buddhist monks built a shrine consecrated with statues of Buddha in one of the deepest rooms.
The cave dwellers of Tham Piew ventured out into the forest only at night. And then, only to gather food, dig for potatoes, or hunt for small game with bow and arrow. Occasionally, a few brave souls would tempt fate and return home to harvest crops from their now-unkempt, bomb-cratered fields. Then, on November 24, 1968 everything changed: a U.S. reconnaissance plane detected activity near the cave.
One of the few survivors, Nang Boua, who was just 13-year-old at the time, remembers: “One night I heard a terribly loud explosion far from my village. I knew there were some people who had refused to leave their homes and were still living in their villages. My grandfather was one of them. The next day, bad news arrived: our village had been bombed and our old house was on fire. My grandfather was severely injured. My auntie rushed back to our village to check on him, so I went with her. We had spent three nights in our burning village when the worst news came.”

While Nang Boua was hiding with her aunt and wounded grandfather next to the smoldering ruins of their family home, Tham Piew had been discovered. She only heard the plane. What she didn’t know at the time was that the first missile went off target and hit the side of the mountain. The second hit the mouth of the cave opening, giving the pilot a clear view of the long tunnel. The third exploded inside the living quarters, killing 374 people in a flash of fire, flesh, rock, and bone. “The last missile caused the cave to collapse and killed everyone I knew,” remembers Nang Boua. Twelve families were wiped from the earth that day.
Grandfather Wat was born in 1950 and grew up during the hostilities of the “Three Princes” era, when the leftist “Red Prince” Souphanouvong, neutral Prince Souvanna Phouma, and right-wing royalist Prince Boun Oum vied for power following independence from France. By the time he was 14 years old, Young Wat had joined the communist party and was serving as a village soldier for the Pathet Lao.
“I served my village by guarding and protecting it from the enemy. During 1964, the US was bombing all over our country, especially in Xieng Khouang province. The villagers couldn’t stay in their homes; they all fled and hid in Tham Piew cave. In the cave there were mostly elders, women and children. The men had joined the army, aside from a few young, healthy adults whose job it was to find food in the jungle due to the bombing raids.”

On November 24, 1968 at 13:30 p.m. an American pilot shot a missile into Tham Piew cave and killed 374 innocent lives … After the cave collapsed, the Muang Kham district governor assigned village guards and soldiers to bring the dead bodies from Tham Piew cave to be buried. It took them four days because they had to bury the bodies between 7 p.m. and sunrise. The [rescue teams] dug seven huge graves out of bomb craters near the cave because it was faster to bury them that way, although some dug graves near the slope of the cave.
On February 7, 1973, the Vientiane Treaty was signed and the U.S. ceased the bombing campaign in Laos. Grandfather Wat stayed in the area and worked for the Xieng Khouang Ministry of Agriculture until he retired in 1986. For many years, the 71-year-old has served as information secretary at Tham Piew museum.
“Many years later, in 1999, authorities from the local Muang Kham district announced that Tham Piew had been designated a historic site by the central government. And on November 24, 2001—the 33rd anniversary of the massacre—Tham Piew was declared a national memorial site dedicated to the innocent lives lost during the Secret War. A ceremony was held and the presiding holy monks chanted for the lost lives.”

Though his fate is tender of the flame of remembrance, he confesses: “It has been hard for me, for all of us who fought against the U.S. during the war. I’d like people to visit Tham Piew to learn about this history and the damage caused by the U.S. bombings.”
Noudaeng was a 29-year-old soldier patrolling a jungle path one morning in 1972 near Xieng Khouang province, not far from the Vietnamese border, when he stepped on a landmine. “The explosion nearly blew my leg off, and my body was hurled into the forest.” Near the border at the time, Noudaeng was rushed to a nearby hospital in Vietnam, where surgeons managed to save his life but had to amputate his leg. “When I came home,” remembers the now 78-year-old Noudaeng, “I felt trapped. I couldn’t walk. I had to use crutches. But it’s really difficult to plow the land and follow the buffalo with crutches! Then I had an idea. I fabricated a homemade leg with bamboo.” He laughs, “I thought I was the first man to invent a prosthetic leg!”
With every passing monsoon the landmines and unexploded ordnance (UXOs) left behind from the Secret War settle deeper into the soil. Of the 80-90 million bombs dropped on Laos that did not detonate upon impact, only around 1 percent have been cleared. Mines Advisory Group (MAG) Laos deminers, dogs, and machines cleared more than 20,000 landmines and UXOs from nearly 9 square kilometers of land in 2020 alone.

Sarah Goring, Public Information Manager at MAG Laos, recalls visiting a village in Xieng Khouang, where she watched MAG clearance teams remove 65 bombs from one schoolyard. Some of the rusted explosives were discovered embedded in the soil beneath the playground. “Teachers and kids were going about their normal routine, despite the fear.” It can be considered a stroke of good luck, given that more than 20,000 people have lost their lives to landmines and UXOs since the war ended in 1973.
Between 1993 and 2016 the United States allocated around $100 million to clearing unexploded bombs and landmines in Laos, which equates to around 1/500th of the nearly $50 billion spent on the Secret War. When Obama became the first sitting U.S. president to visit independent Laos in late 2016, he pledged $90 million over three years to escalate the clearance missions, stating “I believe the United States has a moral obligation to help Laos heal.”
Lamentable though it may be, the “Secret” War is an appropriate name. Very few are aware of the covert U.S. bombing campaign in Laos and no mention of the incident at Tham Piew can be found in wartime news reports. Only Grandfather Wat, Nang Boua, and a handful of witnesses and rescue team members can speak to the tragedy with any real authority. Their generation will go to their graves with some solace, knowing their sacrifices and enduring traumas helped create a nation. Victory, however, will remain bittersweet––as will the obligation of the U.S. remain incomplete––until the remaining tens of millions of UXOs are eradicated from the soils of Laos.
*Interviews have been lightly edited for brevity and clarity.