In January 1967, when the First and 25th Infantry Divisions of the United States Army began Operation Cedar Falls, their all-out offensive against the Communist strongholds of the “Iron Triangle” northwest of Saigon, Vo Thi Mo, 20, was ready.
Born in Cu Chi, in the middle of the Cedar Falls battle zone, Ms. Mo had been in the fight against American troops and the Army of the Republic of Vietnam — the South Vietnamese force, known as ARVN — since the age of 13, when she helped to build the extensive tunnel system that southern Communist forces, known as the National Liberation Front (and to its enemies as the Vietcong), used as barracks, command center and communications network.
By 1967 she was a “deputy of hamlet combat,” and 50 years ago this month she led three commando squads against a battalion of the 25th Division.
“I had never been at any military school,” said Ms. Mo, now 70 and still living in a small house in Cu Chi. “As a girl, I was so scared when I cocked a gun for the first time. But, you know, I learned a lot on the battlefields.”
That poorly equipped, poorly supplied Communist forces were able to resist a sustained mechanized onslaught was a testament to the resilience, adaptability and tenacity of fighters like Ms. Mo. Their ability to survive, at a terrible cost, and learn from the experience helped shape their strategy for the rest of the war.
To understand the experiences of Vietnamese on both sides of the war, I’ve studied hundreds of Vietcong reports and communications, soldiers’ diaries and letters, captured by the Central Intelligence Agency and the Army of the Republic of Vietnam and archived at Texas Tech University. I’ve also conducted dozens of interviews in Vietnam in which former soldiers like Ms. Mo reflected on the war, and Cedar Falls in particular. Besides Ms. Mo, the other interviewees spoke on condition that their initials, but not their names, would be published.
Even a half-century later, Col. Q.T.N., an 81-year-old former regiment commander and one of the few survivors of a division that was considered among the most hardened units of the Vietcong, shuddered as he recalled Cedar Falls in an interview at his home in Saigon, now known as Ho Chi Minh City.
After bomb and rocket attacks from B-52s, jet fighters, helicopters and heavy artillery secured the area, American tanks and troops came in “to search for and destroy us,” Colonel Q.T.N. said. “The lands of Cu Chi, Ben Cat and Ben Suc” — villages at the perimeter of the Iron Triangle — “were razed as if they were some evils peeled off the skins of our body. Therefore, we called the operation Peeling the Shell of the Earth.”
He added: “Although they could not eliminate our leadership, they destroyed our bases, especially war supplies. To be honest, they created many difficulties for us and established a secure perimeter for themselves in the northwest of Saigon.”
Like the colonel, Mr. Q.H. has traumatic memories of the offensive. Born in Cu Chi in 1948 and educated at the University of Saigon, he went to the jungle to join the local Communists’ department of propaganda and training.
“The areas around Ben Cat and Ben Suc shook violently like there was an earthquake,” Mr. Q.H. said. “Because all the food supplies were captured or destroyed, we had nothing to eat and drink. I don’t know how and why I was able to survive the rain of bombs and the storm of fire pouring on us.”
Among the 350,000 documents that American and South Vietnamese forces captured during the operation are many showing that starvation was at the heart of the Communists’ concerns. Because the offensive was so fierce, their comrades near the village of Phuoc Hiep “did not dare to visit to collect rice,” Vietcong officials wrote in reports in mid-January 1967. Living under American surveillance after being relocated to a “New Life Hamlet,” the people in Thanh Hoa did not sell rice anymore, the officials wrote, “so we found it very difficult to survive.”
Many Vietcong escaped the ruined tunnels and hid along rivers and canals. “The Vietcong usually sank themselves in the mud along the canal banks,” a deserter told his interrogators, according to a report I found in the archives. “They had learned, from experience, that South Vietnamese soldiers would not check the canal banks very closely.”
But escape often proved impossible, and casualties rose. The Saigon River became a floating graveyard. In a memoir, Le Dinh An, a veteran of a South Vietnamese unit, wrote of “a river full of death.”
“Cadavers swelled, the men faced down in the water, while the women faced the sky,” he wrote. “When we moved into the new areas, we continued to see new dead bodies floating on the rivers, the banks and paddies. The corpses showed up everywhere.”
By the end of Operation Cedar Falls, American officials said 750 Vietcong were killed, along with 72 Americans and 11 South Vietnamese.
In their official writing, the Communists claimed that during the 19 days of the operation, their forces had resolutely fought the enemy advance of 30,000 United States and South Vietnamese troops. In reality, American and South Vietnamese troops faced only skirmishes against small units, not the main forces of the Vietcong.
Colonel Q.T.N. admitted that his elite division — which he referred to as the “Vietnamese Big Red One,” in homage to the American First Infantry Division — did not engage with the Americans during this operation.
“Our policy was to avoid the enemy and protect our force,” he said. “Only our local guerrilla units coped with the enemies, mainly by hit-and-run tactics. They also concealed their fighters during the day while moving and ambushing the American soldiers at night.”
That was a matter of necessity, said Mr. U.V.M., a former guerrilla at Cu Chi, born in 1947. “How could we fight them while we did not have enough weapons?” he said in an interview. “We avoided them from 6 a.m. until 3 p.m. every day because during that time they carried out their search and destroy missions. We could have been killed anytime if they found us. Our commune was located on the soft ground, so we did not have tunnels. It was more difficult for us to face the bombings and rockets. We secretly sheltered in the bamboo hedges.”
Still, the guerrilla fighters were able to blunt the American attacks, especially in areas around Cu Chi.
Young Ms. Mo’s readiness to resist there came from more than just her years of training and experience. Communist officials had warned her what was ahead before the first American troops entered her hamlet.
“We knew when, where and how many days they would carry out their operation,” she said, smiling. “We had a lot of agents who worked at the Dong Du base of the 25th Division, and in Saigon, who collected information and sent it to us.”
Still, resistance was difficult. “How could our 30 gunners, including six or seven sisters” — fellow female soldiers — “fight a battalion of the Tropic Lightning Division with their helicopters, artillery and planes?” Ms. Mo asked, using a nickname for the 25th Infantry Division. “If we fought them as a regular team in a conventional war, we would be swallowed by their forces.”
Instead she established elaborate defenses, beginning with anti-tank mines. Her fighters used a locally improvised anti-tank mine that was more effective than Soviet mines that worked only when a tank ran right over them. The jury-rigged mines used a remotely activated bamboo lever to propel the mine against the tank. They were devised with explosives from dud American shells gathered on the American Army base or on battlefields. “We stuffed the gunpowder into a galvanized pail or a machine-gun can,” she said. “Our lever mines were very sensitive, so they could easily blast any vehicles.”
But that wasn’t all, she said. “Next, we had an anti-tank ditch, then a spike-trap system, and finally bamboo barriers before our tunnels. So, their tanks could not overcome our anti-tank trenches and mines, while their troops were scared to come in. When they fired at us with cannons and B-52s, we hid in the tunnels. When their troops attacked with tanks, we came out to snipe at them.”
One reason for her tenacity was that, unknown to her enemies, a regional military command and a local Communist Party cell was garrisoned in her hamlet. “We saved our leadership until the operation concluded,” she said.
Despite her lethal efficiency, Ms. Mo did not dehumanize her foe: “I was not scared of the enemy. I fought against them to the end. I felt hatred toward them but I also saw their young men were to be pitied.”
A year before Cedar Falls, she recalled, she saw four soldiers from the First Division sitting in a clearing because they feared booby traps set under the trees. “They did not know they sat on a mine we made from a 105 millimeter cannon shell,” she recalled. “My messenger boy wanted to kill them, but I resisted because I saw they cried as they looked at letters and pictures that I guessed came from their families. I felt sorry for them. My messenger boy asked me why I fought against the Americans but didn’t kill them. He wanted to kill them so we would be awarded the Military Victory Medal. I told him, ‘If you kill them, I will kill you!’ I thought they might be students in their homeland but they were drafted, so they came here to fight. I did not kill them although I knew I could be disciplined.”
Even Mr. Q.H., the Communist propagandist, provided a surprisingly sympathetic view of the American military. “Frankly, we exaggerated stories of the brutal activities of the Americans and the numbers of American killed,” he said. “At that time, we needed that talk in order to encourage our comrades on the battlefields.”
Mr. U.V.M., the former guerrilla at Cu Chi, concurred. “I harbored hatred for the U.S. Army because my brother was killed by them,” he said. “But I recognized that American soldiers valued humanitarianism. When they saw our villagers, even our comrades, wounded they cared for all on the spot or sent them to the hospital immediately.”
While Cedar Falls provided these soldiers with insight into their enemy, it also provided the Communists with insights into themselves.
Colonel Q.T.N. said that after Cedar Falls, National Liberation Front officials changed their strategies in the southeast battlefields and reorganized their forces in ascending levels — hamlet, village, commune and district combat units.
“These units linked together to establish a combat system that could support each other effectively in containing and fighting against the Americans on the battlefields, including the Tet offensive of 1968,” he said. Also, he added, instead of storing weapons that were sent from the north, all were delivered to the local units.
“Therefore, when the Americans carried out next operations, they could not destroy our military supplies, while we had enough weapons to encounter them.”
The colonel remembers Cedar Falls with pride as well as horror. The American and South Vietnamese forces had little to show for their efforts in Cedar Falls, despite their overwhelming firepower and heavy Communist casualties. The tunnels were damaged but mostly not destroyed.
“It was horrible, fierce,” he said of the brutal standoff, “but glorious.”
Hai Nguyen is a doctoral candidate in history at Texas Tech University and a research associate at the Texas Tech Ethics Center.