Vietnamese troops in Kampong Cham before their withdrawl from Cambodia in late 1989. Vietnam's invasion of Cambodia in December 1978 drove the murderous Khmer Rouge regime from power and began a decade of foreign occupation in the Kingdom

Paul Millar
December 25, 2018

“I was present in Cambodia from the beginning to the end of the war,” he said, a thin cigarette loose between his fingers. “Before that, I was a poet.”

"Sitting in the backroom of a Ho Chi Minh City restaurant, Nguyen Cong Trung still looks every inch the soldier. His black hair is parted with military precision above a stern face blinking beneath thin gold glasses. Like many of the soldiers who threw themselves into the maelstrom of Cambodia’s civil war, Trung was only a teenager when he went to fight."

"On the Vietnamese side, these first encounters between young soldiers fighting to repel the forces of Pol Pot and a half-starved people desperate for deliverance were a revelation. Armed with an easy smile and a ready laugh, Nguyen Van Trong doesn’t seem like a man who has witnessed the atrocities of the Khmer Rouge first-hand."

"From the start of his drawn-out days in exile in Vietnam, Sin Khin had heard whispers of a resistance movement among the Cambodian refugees struggling to eke out a living in the camps across the border. Before long, after he had risen to the head of his refugee camp, he was approached by like-minded people looking to strike back against the Khmer Rouge."

"Stiff-backed and scowling beneath steel-grey hair, Dr Hoang Cat is one veteran of the campaign who chose to settle in Cambodia. Once a young combat medic stitching up soldiers maimed by the assault against the Khmer Rouge forces in Kampong Cham province, Dr Cat now works at a Vietnamese-Cambodian hospital in central Phnom Penh."

"“I spend a lot of time arguing with young people online,” he said. “They don’t know about what we really did in Cambodia – they hear about the bad aspects but they don’t hear about the good aspects of us being there. We always behaved very well [toward] the people – we loved them as our relatives. We called the old women mother, we called the younger people brother and sister – and that’s how we were. But the young don’t know about that.”

Full https://southeastasiaglobe.com/vietnams ... -veterans/

That may be true of some VN during their occupation.
But they also beat my wife's father to death in 1980 for going out into the rice fields to fish one night.

A very mixed blessing for many Cambodians - but for me the bottom line is probably that they removed the Khmer rouge when nobody else was prepared to do so. (even if it was not for noble reasons)

They also armed and trained the Khmer Rouge, fought by their side and congratulated them when they took Phnom Penh. Had it not been for arms carried down Uncle Ho’s trail Pol Pot would not have hardly had a bullet to fire. Khmer Rouge were subordinate to the Vietnamese soldiers and fought alongside them until 1972.

As some Cambodians say, “They started the fire then credited themselves for putting it out.”

By marriage, (see above post) i am no friend of VN adventures in Cambodia.
But they did fall out with the KR very quickly.

And they didn't go round strong-arming the majority of the "free world" to keep supporting the KR in the UN until 1990.