Going beyond the politics of bisexuality.

Time heals all wounds, and the battle over bisexuality, so fierce in the late 20th century, has faded during the past 30 years. "Bisexuality exists!" and "We're all really bisexual!" were battle cries of the past. We look back from 2027 and wonder what we were fighting over.

What we were fighting over was politics. The battle wasn't really about bisexuality at all. It was about the way we viewed human beings and human potential. Bisexuality was symbol, and it was principle. But the belief in bisexuality was also empirically testable, and that is where we began fighting with one another in earnest.

In the last decade of the last century, serious clinical and biological research into sexual orientation began for the first time in human history. Scientists, wondering if there were genes that created an instinctual attraction to one gender or the other or both, asked thousands and thousands of people about the way they experienced their sexual orientation. As biologists they weren't interested in how culture shapes this instinct, how society makes us view it, and how religion makes us interpret it. They were interested only in the instinct itself, that uncontrollable, unbidden flash of desire.

What they found was that sexual orientation, like another trait called human handedness, was essentially "bimodal." Both traits had instinctual, unchosen majority orientations (right-handedness and heterosexuality), and both had minority orientations (left-handedness and homosexuality). And both had much smaller orientations (ambidexterity and bisexuality). Virtually no men were bisexual; bisexuality was almost exclusively a phenomenon found in women, and in most of them it was instinctual, unchosen, as well. And the data was quite clear and consistent on this.

Now you, of course, from your perspective well into the 21st century, find this unremarkable. For you, the fact that most people are born straight; that a much, much smaller percentage are born gay; and that the smallest percentage of all are born bisexual (and almost all of those women) is just ... well, it's about as surprising as the distribution data of handedness. But it didn't used to be like that.

And the reason was, as I've said, politics. Politically, the Right and Left, now as then as 400 years ago and since the beginning of the modern age, have fought over the Question of Human Nature: Why are we human beings what we are? The two competing answers, the answers on which all policy prescriptions are based, are: Born or Made.

"Born," said the ultraconservative Victorian social Darwinists (citing Hobbes and Descartes), and so they told the lower classes to stay in their places because they were born to them, women to accept a secondary role that was natural, nonwhites that nature had made them the colonized. They saw an inherent, biological inequality among people.

"Made," said the ultraliberal Marxists (citing Locke and Rousseau), and so they held that if only we could change the society that made us--nationalize production, educate the masses, equalize environments--we could create equality among people. Since people were made, they would reflect their environment, and there was always a potential social equality among people.

This debate was very much alive in 1997. It surfaced every time someone on the Left proposed a social program (and higher taxes to pay for it) and someone on the Right opposed it. And so what did the research say--Born or Made? Into whose arsenal did it slip like a slim, potent little weapon?

It was a weapon in the armamentarium of the conservatives. A growing body of biological research said: Born. It said: The conservatives are right. Culture and environment may shape the way the trait of sexual orientation is expressed as they determine whether the behavior resulting from the biological trait of handedness is expressed by picking up chopsticks or a fork. But the trait itself--sexual orientation, handedness--is determined by biology. It is inborn.

And it was, therefore, part of a furious battle that raged in that now-far-away century. There was back then a best-selling book arguing that IQ was to a certain extent genetic and heritable. The Left hated it, saying IQ was determined by environment. There was animal research saying that gender--maleness and femaleness--was to an extent determined by biology, that violence and aggression were inborn. The Left hated it, saying gender was merely a social construction, that aggression was determined by society. The research said: No. We are, to an extent, born this way. And no Head Start, no welfare, no taxpayer-supported social program, no misguided clemency from the bench will change this. They will, rather, demonstrate, as one conservative put it, "the futility of most government interventions to compensate for natural inequalities."

The research into sexual orientation said the same thing. And the Left hated it, believing that society and environment determined the gender to whom you were attracted. The Left hated it because it undermined its own fundamental political belief. And so, the Left said, we are all really bisexual. We all have the capacity for attraction to both sexes, and it is only society that forces us to perceive ourselves as gay or straight.

And why did we gay people fight among ourselves over bisexuality? Why did we scream at each other, why did the research split us apart, why did some of us insist that we were all truly bisexual? Because most of the gay leadership were liberals, warriors on the side of Made. Devout, devoted liberals, for whom the research of sexual orientation in its larger historical sense was utterly vile. They were sincere, well-meaning people who tactically betrayed the gay movement: The one fact that, in the 20th-century American debate over gay rights, was of greatest pragmatic, immediate political utility for gaining gay civil rights from America's voters--the fact that human sexual orientation is basically like human handedness, unchosen and normal and no more "promotable" than eye color--was attached to a body of research that was, on the visceral, fundamental level of political philosophy, utter anathema to them.

They were traitors to the gay and lesbian movement. And so 30 years ago we gay people were a political house divided along the line called "bisexuality," which was actually just the symbol of differing political beliefs. But we came to our senses.

The 21st century's generation of gay and lesbian leaders, the leaders you know now, are more centrist. And they told the American people the truth. Being gay is like being left-handed. Bisexuality is not the way we're all born, a general, malleable capacity that meant sexual orientation was a "lifestyle choice," a promotable thing, something society could change. It was a tiny orientation, as inborn as being gay or straight. And America responded. The accurate understanding of sexual orientation helped us pass gay rights laws. It gave our allies ammunition. It helped persuade and win over our opponents.

And today no one talks much about bisexuality anymore.

Burr is the author of A Separate Creation: The Search for the Biological Origins of Sexual Orientation. His work has appeared in The Atlantic Monthly, The New York Times Magazine, The Washington Monthly, and The Weekly Standard.