During tumultuous protest demonstrations in Ho Chi Minh City on June 9 and 10, Vietnamese police detained a 31-year-old American graduate student, Will Nguyen. Photos of his being roughed up by plainclothes police auxiliaries and dragged off to jail with an orange bag over his head went viral on the internet.

Within a few days, while Nguyen was being grilled incommunicado by his captors, his plight captured the attention of US media and members of the US Congress. His family and friends from his undergraduate days at Yale University testified to Nguyen's excellent character and his love for the land of his ancestors. At last on June 14, the police announced that they were building a case against Nguyen for ''disturbing public order."

On June 15, American consular officers were allowed to meet with him. He later confessed on television, possibly under duress, to having blocked traffic and caused a public disturbance.

None of the reports, whether in media supervised by the Hanoi regime, in dissident media online, or in the Western press, have offered any plausible explanation of why Vietnam's police chose to mete out such extraordinary treatment to this second-generation Vietnamese-American scholar.

A 3,500-word English-language essay posted online by Nguyen on April 30, and then on May 23 in translation offers a clue. In "North/South," he relates his lengthy effort to disentangle a coherent narrative of Vietnam's recent history from ''contradictory but co-existing truths." On one hand were the bitter accounts of struggle and betrayal that he absorbed while growing up in Houston's ''Little Vietnam," and on the other the triumphalist Hanoi propaganda that Nguyen found in his university library.

The full texts of Nguyen's essay are online at https://newnaratif.com/journalism/north-south/. Note that the Vietnamese translation was published only a few weeks before his arrest. Here, I'll replay only Nguyen's summing up:

For South Vietnam (since 1975), the loss is more political than cultural: no longer do citizens possess freedom, democracy, and a vibrant civil society. Even if imperfectly practiced in South Vietnam, greater freedom of expression brought prosperity and a society of better quality than what Vietnam has today. Many Vietnamese, unable to express dissatisfaction with the status quo at the ballot box, vote with their feet. Leaving the country is the dream for those who have means to do so; Hanoi readily acknowledges that Vietnam suffers from brain drain.

Even so, it must be acknowledged that the war was a manifestation of North and South both wanting the best for the Vietnamese people while choosing drastically different paths. It would be unforgivably cynical to believe otherwise, to view either government as monolithic entities not made of Vietnamese individuals who loved their country. The root of the conflict stemmed from both sides competing to be the only good. Both the North and the South had causes they believed to be just—a fact which native and overseas Vietnamese have yet to fully accept.

On paper and in diplomatic circles, there is only one “true” Vietnam. Although the Republic of Vietnam ceased to exist after 30 April 1975, it lives on in the hearts and minds of millions of Vietnamese who abhor communist totalitarianism. It lives on in its enforced absence within Vietnam’s national discourse. A silent, de facto ban of the yellow flag with three red stripes, of any positive mention of the southern republic, of anything related to the former state is, in a way, perpetuating South Vietnam’s existence. And if history is any indication, the South remembers.

It may be that in searching Nguyen's hotel room or in interrogating him for long hours, Vietnam's police have found other reasons why Hanoi needs to indict this young scholar, to try him, sentence him and then, probably, to extract his agreement that, if permitted to leave Vietnam, he will never return.

Until the Ministry of Public Security permits us to scrutinize such evidence, I'm inclined to think that Nguyen has been arrested and, however the charges are stated, he will be punished in fact for heresy.

Forty-two years after the fall of Saigon, the winning side refuses to concede, or indeed to allow its historians to assert, that there are significant cultural differences between the north and the south of Vietnam, that the thirty-year conflict that convulsed Vietnam was in important respects a tragic civil war, that Hanoi's feckless ''reconstruction'' of the vanquished south left permanent scars, and that ''the root of the conflict . . . stemmed from both sides competing to be the only good.''

David Brown is a former US diplomat with extensive experience in Vietnam and Southeast Asia. He is a regular contributor to Asia Sentinel.