The book also contains two big themes that Cheevers weaves throughout more than 600 pages of text: His against-the-grain assessment of Ngô Ðình Diệm as a strong leader, and his fiercely negative characterization of what he calls a “cabal” of Kennedy advisers who underhandedly all but forced JFK to greenlight U.S. support for the coup.

Cheevers argues that Diệm, widely regarded by historians as a corrupt, brutally authoritarian, and ineffective leader, had his good points. Diệm, he writes, was South Vietnam’s “toughest, most experienced leader,” a “stout-hearted” man and a “bold, durable president” who led “a relatively stable government.”

He approvingly quotes U.S. Ambassador to South Vietnam Fritz Nolting (a diehard Diệm supporter) saying that the quirky South Vietnamese leader was “an honest ally.” He repeatedly cites another fan, William Colby (“always a perceptive observer”), who was the CIA Station Chief in Saigon and who, Cheevers says, admired Diệm’s “strength and leadership.” And he quotes the clueless, disgraced MACV Commander Gen. Paul Harkins extolling Diệm’s “strength of character.”

Cheevers devotes a large part of the book to the Buddhist Crisis of 1963, during which Diệm and Nhu brutally cracked down on anti-government Buddhist leaders and their followers. Oddly, though, Cheevers claims that Diệm and Nu engaged in no “systematic government persecution” of the Buddhist minority that tumultuous spring and summer.

His analysis of that portentous situation includes few positive words for Thích Trí Quang, the Buddhist monk who led the uprising. Cheevers portrays him as a politically savvy manipulator whose goal was to overthrow Diệm.

Cheevers also is a fan of the Diệm regime’s controversial Strategic Hamlet program, which he says was an effective way to fight communism and just might have worked if Diệm had not been overthrown. That assessment flies in the face of the conclusions of many U.S. military advisers in Vietnam in 1963 and historians since then that the program—in which rural Vietnamese were uprooted from their ancestral villages and sent to live and work in barbed wire enclosed “hamlets”—did little or nothing to convince the populace to support the Diệm regime.

Despite his cheerleading, Cheevers offers many examples of Diệm’s and his brother Nhu’s decidedly autocratic and anti-democratic policies. That includes press censorship; the imprisonment of tens of thousands of political enemies and critics of the regime including journalists and high school and college students; flat-out corruption; and not-infrequent torture and assassinations in secret police prisons.

In 1963, Cheevers notes, the Diệm regime “hardened into a sclerotic family clique with fading public support,” with the eccentric president becoming “more isolated, more authoritarian, and more reliant on his family for support and advice.”

Cheevers saves his most damning analysis for what he variously calls a “clique,” an “anti-Diệm coterie,” and a “cabal” of “devious” State Department “underlings” who “pulled the rug out from under a longtime anti-communist ally during wartime” and convinced President Kennedy to green-light U.S. acceptance of a coup.

Assistant Secretary of State for Far Eastern Affairs Roger Hilsman, (whom Cheevers tars as “a third-tier State Department bureaucrat”) a World War II OSS veteran, heads Cheevers’ list, which also includes Under Secretary of State for Political Affairs Averill (“The Crocodile”) Harriman; Michael Forrestall, a member of JFK’s National Security staff; and Henry Cabot Lodge, whom JFK appointed to be U.S. Ambassador to South Vietnam in August 1963.

There’s little doubt that those men (“coup touts,” according to Cheevers) were strong Diệm critics who came to believe his massive unpopularity weakened the fight against communism and that it was in the best interests of the United States for Diệm and Nhu to be replaced. But Cheevers all but dismisses their views and reduces them in the book to a conniving, devious clique.

The fact is, as Cheevers himself shows, much of their advice to Kennedy took place in many meetings that also included Diệm supporters, mainly National Security Adviser Maxwell Taylor, Defense Secretary Robert S. McNamara, Diệm diehard Nolting, and Colby. It’s hard to buy the contention that the anti-Diệm group were a scheming cabal. They could easily be characterized as a chorus of informed Kennedy advisers who aired their views, alongside those of the Diệm regime’s outspoken backers.

Regardless of how the coup came to be, there’s no disputing that it went catastrophically wrong when the Ngo brothers were brutally murdered instead of being allowed to leave the country. Within days, the generals began bitterly quarrelling among themselves.

More coups followed until Thiệu took authoritarian control in October 1967. With American support, he reigned supreme until fleeing the country a few days before the war ended with a communist victory on April 30, 1975.