From the streets of Beijing to the girlie bars of Bangkok, my exploration of the erotic tension that links East and West blurred the line separating fantasy and reality.

Given that the book’s subject is sex, the natural question I’m asked is what my research was like, and the answer, perhaps disappointing, is that most of it was done over dusty volumes of forgotten lore in the Allen Room of the New York Public Library. But not all of it. There was field research as well, like the evening I spent in Bangkok two years ago when I interviewed the person identified in the text as Dave the Rave. He is the British-born manager of AngelWitch, a girlie bar in the Nana Plaza, one of the several places in Bangkok where the historical encounter of sexual cultures that is the book’s main concern is enacted in a vulgar, contemporary way. Most of the customers, who included a fair sprinkling of pasty and potbellied middle-aged men, kept their gaze upon the phantasmagorical scene before them, but I kept my head down in order to note Dave’s worldly wise comments in my spiral pad, including his caution against the futile hope of many Western men that they are going to find true love in Bangkok, rather than just sex.

Read an excerpt of Richard Bernstein’s The East, the West, and Sex: A History of Erotic Encounters.

I also interviewed a couple of Thai ex-prostitutes and quite a few American men who had lived the part of my history that took place in post-World War II Asia, especially Vietnam. In addition to Bangkok and the Thai beach resort of Pattaya, I went to Ho Chi Minh City, Danang, Na Trang, and Haiphong. I visited Singapore, the Malaysian port town of Malacca, and Beijing, where I talked to a half-dozen or so Chinese women on why they prefer Western to local men.

And, though I didn’t know it at the time, I was also doing field research during the eight years I lived in Asia, between 1971 and 1982, when I worked in Hong Kong and China for Time magazine, and, before that, studied Chinese in Taiwan. There was a fellow American language student I knew in Taiwan, the kind of guy who wouldn’t have done all that well in the erotic competition back home, but he had a dazzling local girlfriend. It’s not that dazzling Taiwan women were there for the asking; it wasn’t quite that paradisal. And yet a certain unearned and undeserved glamour did attach to being a Western person in Asia in those days, and I don’t think that can be explained entirely by the yearning of local women for American green cards, though certainly there was some of that. The glamour was, I believe, a legacy of the centuries of Western colonial domination of Asia, when Western men had the power, and a sexual advantage has always come with power.

Decades later I realized that the situation I’d observed in microcosm on Taiwan was both an old and an enduring story, and one that, while told in numerous bits and pieces, had never been fully put together. I have to admit when I started researching the topic, I worried you could tell the whole basic story on a postcard, and that a book might be an exaggeration. Happily that turned out not to be the case. As I did my interviews and my research in the NYPL, I discovered a rich, pungent, morally complex, and sometimes even moving history, produced by the meeting of the sexual culture of Christendom and what I call the culture of the harem. The former was restrictive and ridden with sin; the other is also restrictive, maybe even more so when it comes to the sexuality of "nice" girls and women, but it is endowed neither with the sense of sin nor the Western idealization of monogamy. The culture of the harem is devoted to the erotic pleasure of men, and many Western men over the centuries have happily adopted it, gone native as it were, once they arrived in the East.

The East, the West, and Sex: A History of Sex. By Richard Bernstein. 336 pages. Knopf. $27.95. Indeed, in doing the research, I was actually surprised by the extent to which this erotic encounter, though not much recognized in standard histories of the relations between East and West, stands at the psycho-cultural nexus of the Western experience in Asia. So many primordial elements enter into the picture, not just the intimate connection between sex and power but also the relation of sex and adventure. I originally thought I might entitle the book The Butterfly Complex, inspired by the opera Madama Butterfly, in which a teenage Japanese girl falls so completely in love with an undeserving American soldier that she kills herself over his infidelity—which seemed to me at the time a perfect representation of the colonialist West’s literal and figurative transformation of the East into a worshipful, compliant woman. In the end I found a different title, but I was astonished to discover that, contrary to what I’d thought, there was almost nothing fanciful about Madama Butterfly, in the telling of the story by Puccini and his librettist. It turns out that more than a few strikingly similar stories actually occurred in Nagasaki, Japan, in the late 19th century—not to mention one I discovered that took place during the post-war American occupation of that country.

And this reveals something about the conventional and politically correct wisdom on the topic of East and West, namely that the West’s experience of the East was largely based on a fantasy, that we collectively gazed at Asia through the prisms of preexisting clichés and imperialistic wishful thinking. There was some of that, surely, but the discovery of my book is that what has been taken to be fantasy was actually real experience.

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Richard Bernstein is a writer based in New York. He was a critic and foreign correspondent for The New York Times for 24 years. His new book, The East, the West, and Sex: A History of Erotic Encounters, will be published by Alfred A. Knopf in June.