The 50-foot Swift boats were easy targets as they plowed through the waterways of the Mekong Delta in packs of three or four, making big waves and thunderous noise when approaching.
Former Viet Cong soldier Duong Hoang Sinh remembers them well -- the one time he tangled with three Swift boats, the Americans killed all the insurgents in his unit except two.
"It was very fierce fighting," said Sinh, 52, who lost his left eye during the war and still has shrapnel in his arm. "Each side tried to eliminate the other."
Sinh and John F. Kerry, the U.S. Democratic presidential nominee, were fighting along the Dong Cung canal about the same time 35 years ago in early 1969, experiencing the intensity of war along these muddy waters, but from opposite sides.
Although Sinh had never heard of Kerry, he had a strong opinion about the debate surrounding the candidate's Vietnam War record as a U.S. Navy Swift boat commander: Kerry must have had guts to troll the Mekong Delta's spider web of rivers and narrow canals knowing that Viet Cong like himself were waiting to pick him off.
"Kerry served in Vietnam and he was awarded the medal for his bravery," Sinh said. "He deserves the medal."
The memories of the Swift boat battles in these waters are now being sharply scrutinized under the divisive lens of the U.S. presidential election, where Kerry's actions under fire have been disputed by a group of veterans.
As a Navy lieutenant, Kerry commanded two Swift boat units, PCF-44 and PCF-94, in Vietnam in late 1968 and early 1969. He was awarded three Purple Hearts, a Silver Star and a Bronze Star.
Kerry's actions in several of those instances -- including a March 13, 1969, incident when he rescued U.S. Army Special Forces Lt. Jim Rassmann under enemy fire; a Feb. 28, 1969, incident when he chased and killed a Viet Cong fighter; and a December 1968 incident when he was wounded -- have been challenged in a series of television ads aired by Swift Boat Veterans for Truth.
The anti-Kerry Vietnam War veterans group contend the Massachusetts senator did not come under heavy enemy fire as his medal citations state. But other veterans of the "brown water navy" who witnessed the fighting, along with Navy documents from that time, have backed Kerry's version of events.
Associated Press took a boat tour along the same rivers and canals of the Mekong Delta that served as a battleground for Kerry. The people who live here now have worked hard to put the fighting behind them, but the memories persist.
When Kerry and Sinh plied these muddy waterways, mangroves grew thick on both sides of the Bay Hap River, forming a bushy shield of impenetrable green. It was perfect cover for Viet Cong guerrillas who lay waiting to ambush the clunky U.S. Swift boats.
Sinh recalled one morning in February 1969 when he and six other insurgents watched silently from their hiding spot in the thick forest that grew along the banks of the Dong Cung canal, about 4.7 miles off the Bay Hap River in Vietnam's southernmost province of Ca Mau.
When the U.S. Navy boats rumbled into view, the Viet Cong were in for a shock as the Americans began firing on them. Sinh recalled his comrade got off one good shot from a B-40 rocket launcher, blasting a hole in the side of one vessel. But it wasn't enough. The Americans charged, unloading a hail of bullets, and Sinh realized this was not a fight his unit could win.
"We got more fire from the American soldiers after that. We tried to fight back, but decided to flee," he said.
He believes the Americans must have had intelligence about the planned ambush that day because the three U.S. boats fired first. Five of his comrades died, including his buddy who fired the crippling blast. Sinh escaped by fleeing into the dense forest.
He said it was the first and last time he fired at Swift boats along the waterways where he grew up. Not long after, he was sent away from his family in Dong Cung village to fight elsewhere, which is why he remembers the date so well. His village was renamed Tran Thoi after the war.
To Sinh and those who still live along the Mekong Delta, the controversy over Kerry's tour of duty in Vietnam is dumbfounding. Since the war ended in 1975, they have reveled in peace and, more recently, economic growth.
"I think it's American politics," said Nguyen Van Khoai, 61, a former Viet Cong soldier who attacked American troops along the water but never fought directly against the Swift boats. "On any side, a soldier who made an outstanding feat is given a medal -- but maybe some people try to think otherwise."
The area that once crawled with Viet Cong has changed. The thick mangrove forests that lined both sides of the Bay Hap River, Dong Cung canal and other tributaries are mostly gone. Some canals just wide enough for the U.S. Navy boats to pass through are double in size today.
Many more thatch houses are perched on stilts along the water's edge and small speed boats now zoom past. Shrimp farms litter the landscape where forests once grew, and the names of many wartime canals and villages have been changed.
Cai Nuoc village, where Kerry put in on March 13, 1969 -- the day for which he was awarded his third Purple Heart and a Bronze Star for rescuing Rassmann -- has ballooned into a district. Cafes abound along the water here as well as shops selling a wide variety of wares, including shiny bathroom tile. A thriving floating market also bustles where mounds of ripe rambutan, pomelo and bananas form a rainbow of color.
But much remains the same. The water is still dotted with children splashing and men checking fishing nets attached to crude sticks poking out of the river. The smell of diesel fuel and smoke is in the air and stinging downpours still come in the afternoon.
Many of the residents here in the Mekong Delta have never heard of Kerry. They do, however, remember the Swift boats and the Americans who roared by aboard them.
"I was very scared when I heard the American boats coming up the canal, so I had to hide in my backyard," said Phu Thi Nguyet, 60, who has lived along the Dong Cung canal since 1960.
For those who have followed the debate, the Kerry controversy is confusing.
"It's very strange in a way. It's just a small thing, but they have made it into a big deal," said Lam The Hung, 42, a native of Cai Nuoc village who now serves as a provincial official in Ca Mau. "The fact that one soldier rescued another -- that happened thousands of times among the Vietnamese, so I don't understand."
Hung said he was also puzzled by the uproar over Kerry's decision to join the antiwar movement upon returning home.
He said Kerry's actions proved that he learned a lot during his time in Vietnam and that he wanted to keep other Americans from dying here.
"When they went home, they knew the nature of the war and the people here were innocent and they knew it was nonsense to wage war here," said Hung, whose two older brothers joined the Viet Cong and laid mines in the rivers where the Swift boats operated.
Although Kerry may be worried about veterans' support in America, Sinh said he would vote any day for his former enemy over President Bush.
In the veteran's opinion, Kerry's experience along these rivers fighting Viet Cong might keep him from sending other young Americans to invade countries.
"He knew the suffering and how much misery it brought to the people of Vietnam -- he knew the cruelty of war," Sinh said. "So I don't think he would go to war again if he's elected."