“Interested readers would like to know why.”
She was a Buddhist in a country that was over 75% Buddhist but she and many others had to hide their religion.
Her classmates ‘disappeared’.
Her neighbors ‘disappeared’.
He was a cruel dictator.
What were her classmates and neighbors doing; what was the VC activity in her area doing? Look at all the Muslims that proclaim they never knew a terrorist in their midst was one; proclaiming in affect their own innocence. Maybe your wife (how old rhen??) did not really know everything that was going on in the area where she lived. Maybe she never knew what some families other than her own were secretly involved in. Being innocent when others around you are secretly not innocent can lead to false perceptions of events that seem implausible at the time.
Just sayin, under many conditions in Vietnam at the time, some things can represent a hiding of reality that seems very foreign, blunt and incomprehensible when suddenly that reality hits. The Viet Cong depended on that, by infiltrating all sorts of “nationalist”, Buddhist and secular protest groups and eventually controlling them. They were always someone’s neighbors.