On Easter Sunday 1967, the most famous American in Southeast Asia went for a short walk in the Malaysian hill station of Cameron Highlands and disappeared, as thoroughly as if he had been taken up into the air and vaporized.

In the intervening 44 years, no trace has ever been found of the then 61-year-old Jim Thompson, a onetime OSS and CIA agent who became known as the Silk King of Thailand. The disappearance has become one of Asia’s enduring mysteries. It is one of the most complete evaporations ever recorded. Nor has Joshua Kurlantzick, a Fellow at the Council on Foreign Relations in New York, been able to come any closer to finding him.

But Kurlantzick has nonetheless spun an engrossing 256-page book, heavily footnoted and titled The Ideal Man: The Tragedy of Jim Thompson and the American Way of War (Wiley; 253 pp, hardcover, $25.95) out of the story. The book is more than a simple recitation of Thompson’s life. It is a well-researched account of how the United States, against Thompson’s advice, went tragically wrong in Southeast Asia and ended up in the Vietnam War. Thompson himself was caught up in a titanic battle for the soul of Southeast Asia and lost, no matter that he would become vastly wealthy by revitalizing Thailand’s silk industry.

In a time when calling someone a legendary figure has become a cliché, Thompson, born of a wealthy Delaware family, was truly legendary. As a member of the OSS under its director, William “Wild Bill” Donovan, Thompson in World War II won five Bronze Stars and other medals, operating behind German lines blowing up bridges and ambushing Nazi troops.

A solitary figure whose wife ran away with another man and divorced him while he was overseas, Thompson moved to Thailand to build a network of spies and operatives that stretched across Laos, Vietnam and Cambodia as well as Northeastern Thailand. He would never live in the United States again. He came to believe that the Vietnamese leader Ho Chi Minh would turn his country into a bulwark for democracy, as would Pridi Banomyong in Thailand and Prince Souphanouvong, the so-called Red Prince of Laos. Thompson and his fellow OSS agents in the immediate aftermath of World War II were there to help implement the vision of the late President Franklin D. Roosevelt, who felt that none of the countries were to be handed back to the French, British and Dutch colonial powers. They saw the nationalists as their natural allies.

Roosevelt died in 1945, to be replaced by the hard-line Harry Truman and later the Republican Dwight D. Eisenhower. And, Kurlantzick writes, “in just a few years Washington would be arming the French to fight these same men and some of Thompson’s ideas about the Vietnamese or Laotian nationalists would appear to American hawks like treason.”

A good deal of the shift in policy can be laid at the door of a man named Willis Bird, who like Thompson had served in the OSS, “had seen opportunity in Asia after the war and had never gone home.” The parallel stories of Bird and Thompson inadvertently form the heart of this book. And if anything, Bird, a shadowy figure who took pains to maintain his anonymity while making himself rich, is even more intriguing than Thompson.

Bird, Kurlantzick writes, “using his wartime connections with old OSS friends, now scattered around the globe, would import paper, insecticides, glass, building materials, and almost anything else needed in Bangkok.” His connections throughout Southeast Asia would rival Thompson’s.

“When Bill Bird soon turned his attention from glass and pesticides to US intelligence, his plans, his practicality, and his innate sense of politics and scheming soon mattered much more. Soon he would be running his own private intelligence operation out of Bangkok, rivaling Jim Thompson for influence.” Bird would ultimately describe Thompson, a onetime friend, as a naïve fool.

Thompson, according to classified cables, argued that “Washington, working with Pridi’s government (in Thailand), could blunt Soviet inroads in Southeast Asia by backing the Vietminh, who desperately sought ties to America. “

The rest, as they say, is history. William Donovan, pushed out of what would become the CIA, became the ambassador to Thailand. He would not back Thompson. In the United States, rising anti-communist hysteria fueled by the late Sen. Joseph McCarthy began to determine foreign policy. President Dwight Eisenhower fatefully decided to aid the French, who were destroyed at Dien Bien Phu and were pushed out of Indochina. America took on the role of stopping the nationalists, who sought support from the then-USSR and China after being given the cold shoulder by the US. Some 57,000 Americans and perhaps a million Vietnamese would ultimately die as a result of that folly.

Thompson sought to influence US foreign policy against the hawks, culminating in his alienation from the US Embassy in Bangkok, which in addition to backing the war over the border across what had been Indochina, condoned Bangkok’s brutal and corrupt generals, generations of whom have continued to run the country to this day. Thompson’s friend and colleague Pridi would be driven out of the country into exile.

Bird, “less romantic than Jim Thompson, saw, too, that the conservative forces in Thailand, the army, the royalists, Philbul – still had a lot of power. If he was going to survive in Thailand, he shouldn’t alienate anyone.” Bird didn’t. He actively sided with the authoritarians, among other things participating with Claire Chenault in the development of the fabled Civil Air Transport, the CIA-supported airline that eventually would become Air America, flown by pilots on contract to the CIA.

In the meantime, Thompson began to take an interest in silk. He became wildly successful, with his silk creations making it all the way to Broadway and Hollywood in the play The King and I and in other plays and movies. And, while he developed the industry, he made sure that the growers and weavers of the Northeast participated in the profits, which alienated him from the powerful Thais who had exploited them for centuries.

Thompson would maintain a fabulous house in Bangkok, regenerating interest in graceful Thai architecture as well. The house, filled with fabulous artwork, is visited to this day by legions of tourists. He entertained guests almost every night, including dignitaries, movie stars, generals and others – as Kurlantzick points out, feeding them what they thought was exotic delicious food, which his servants simply went out every night and bought in street stalls.

As his counsel was sought less and less by the US Embassy, and as suspicion grew that he was a traitor and perhaps even a communist, Thompson grew alienated, sick and bitter. Exhausted, he opted for an Easter vacation in the Cameron Highlands. His disappearance led to perhaps the biggest manhunt in Asian history, with his family continuing to hunt for him for three decades.

Was he murdered? Did a tiger get him? Did he commit suicide somewhere in the bush? In the 1960s, the Cameron Highlands was much more heavily forested than it is today and it was theoretically possible for a man to disappear. But Thompson had made a flock of enemies – in the intelligence community, in the Thai business community, particularly in the silk industry.

“Thompson’s combination of mystery, power, idealism, glamour and, eventually, failure, transfixed one generation after the next and led to continued interest in what had happened to the silk king,” Kurlantzick writes. However, it is unlikely that his fate will ever be known.