With its decision in Obergefell v. Hodges, the Supreme Court has brought the sexual revolution to its apex—a redefinition of our civilization’s primordial institution, cutting its link to procreation and declaring sex differences meaningless. The court has usurped the authority of the people, working through the democratic process, to define marriage. And it has shut down debate just as we were starting to hear new voices—gay people who agree that children need their mother and their father, and children of same-sex couples who wish they knew both their mom and dad.

If the polls are right, there has also been an astonishingly swift change in public opinion. Most Americans now think that justice, equality, or at least good manners requires redesigning marriage to fit couples (and at this point, just couples) of the same sex. Or at least they’ve been intimidated into saying so.

I argue in my just-released book, “Truth Overruled: The Future of Marriage and Religious Freedom,” that we are sleepwalking into an unprecedented cultural and social revolution. A truth acknowledged for millennia has been overruled by five unelected judges. The consequences will extend far beyond those couples newly able to obtain a marriage license.

If our society teaches a falsehood about marriage, it is harder for people to live out the truth of marriage. Marital norms make no sense, as a matter of principle, if what makes a marriage is merely intense emotional feeling, an idea captured in the bumper-sticker slogan, “Love makes a family.” There is no reason that mere consenting adult love has to be permanent or limited to two persons, much less sexually exclusive. So, as people internalize this new vision of marriage, marriage will be less and less a stabilizing force.

If fewer people live out the norms of marriage, then fewer people will reap the benefits of the institution of marriage—not only spouses, but also children. Preserving the man-woman definition of marriage is the only way to preserve the benefits of marriage and avoid the enormous societal risks accompanying a genderless marriage regime. How can the law teach that fathers are essential, for instance, when it has officially made them optional?

The essence of marriage as a male-female union, however, has become an unwelcome truth. Indeed, a serious attempt is well under way to define opposition to same-sex marriage as nothing more than irrational bigotry. If that attempt succeeds, it will pose the most serious threat to the rights of conscience and religious freedom in American history.

Bigots or Pro-Lifers?

Will the defenders of marriage be treated like bigots? Will our society and our laws treat Americans who believe that marriage is the union of husband and wife as if they were the moral equivalent of racists?

Perhaps not. Think about the abortion debate. Ever since Roe v. Wade, our law has granted a right to abortion. Yet, for the most part, pro-life citizens are not treated as though they are “anti-woman” or “anti-health.” Those are just slurs from extremists. Even those who disagree with the pro-life cause respect it and recognize that it has a legitimate place in the debate over public policy.

And—this is crucial—it’s because of that respect that pro-choice leaders generally respect the religious liberty and conscience rights of their pro-life fellow citizens. Until the insurance-coverage mandates imposed under Obamacare, at least, there was wide agreement that pro-life citizens shouldn’t be forced by the government to be complicit in what they see as the evil of abortion. Pro-life taxpayers, for example, haven’t been forced to fund elective abortions, and pro-life doctors haven’t been forced to perform them.

Will the same tolerance be shown to those who believe the truth about marriage? Will the government respect their rights of conscience and religious liberty? It doesn’t look good. So far, the trend has been in the opposite direction. We must now work to reverse it.

For years, the Left’s refrain has been that people who oppose same-sex marriage are just like people who opposed interracial marriage—and that the law should treat them as it treats racists. Indeed, The New York Times reported that while the amicus briefs filed with the Supreme Court in Obergefell were evenly divided between supporters and opponents of state marriage laws, no major law firm filed a brief in support of marriage as the union of a man and a woman. “In dozens of interviews, lawyers and law professors said the imbalance in legal firepower in the same-sex marriage cases resulted from a conviction among many lawyers that opposition to such unions is bigotry akin to racism.”

The False Analogy of Interracial Marriage

Same-sex marriage advocates insist that the court’s Obergefell ruling is not like Roe v. Wade, which engendered undying controversy, but like Loving v. Virginia, the universally accepted decision that struck down bans on interracial marriage—a decision now so uncontroversial that most Americans have never heard of it. If that is true, then anyone who opposes Obergefell is an irrational bigot—the moral and legal equivalent of a racist.

But, as I explain in my book, great thinkers throughout human history—and from every political community until about the year 2000— thought it reasonable and right to view marriage as the union of husband and wife. Indeed, this view of marriage has been nearly a human universal. It has been shared by the Jewish, Christian, and Muslim traditions; by ancient Greek and Roman thinkers not influenced by these religions; and by Enlightenment philosophers. It is affirmed by canon law as well as common and civil law.

Bans on interracial marriage, by contrast, were part of an insidious system of racial subordination and exploitation that denied the equality and dignity of all human beings and forcibly segregated citizens based on race. When these interracial marriage bans first arose in the American colonies, they were inconsistent not only with the common law of England but with the customs of every previous culture throughout human history.

As for the Bible, while it doesn’t present marriage as having anything to do with race, it insists that marriage has everything to do with sexual complementarity. From the beginning of Genesis to the end of Revelation, the Bible is replete with spousal imagery and the language of husband and wife. One activist Supreme Court ruling cannot overthrow the truth about marriage expressed in faith, reason, and universal human experience.

We must now bear witness to the truth of marriage with more resolve and skill than ever before. We must now find ways to rebuild a marriage culture. The first step will be protecting our right to live in accordance with the truth. The key question, again, is whether the liberal elites who now have the upper hand will treat their dissenting fellow citizens as they treat racists or as they treat pro-lifers. While elites disagree with the pro-life position, most understand it. They can see why a pro-life citizen defends unborn life—so for the most part they agree government shouldn’t coerce citizens into performing or subsidizing abortions. The same needs to be true for marriage. And we need to make it true by making the arguments in defense of marriage.

What Do Marriage Defenders Do Now?

In January 1973, the U.S. Supreme Court created a constitutional right to abortion throughout all nine months of pregnancy in Roe v. Wade and Doe v. Bolton. Pro-lifers were told they had lost and the issue was settled. The law taught citizens that they had a new right, and public opinion quickly swung against pro-lifers by as much as a two-to-one margin. One after another, formerly pro-life public figures—Ted Kennedy, Jesse Jackson, Al Gore, Bill Clinton—“evolved” in their thinking to embrace the new social orthodoxy of abortion on demand. Pundits insisted that all young people were for abortion, and elites ridiculed pro-lifers for being on the “wrong side of history.”

The pro-lifers were aging, their children increasingly against them. The only people who continued to oppose abortion, its partisans insisted, were a few elderly priests and religious fundamentalists. They would soon die off and abortion would be easily integrated into American life and disappear as a disputed issue.

But courageous pro-lifers put their hand to the plow, and today we reap the fruits. My generation is more pro-life than my parents’ generation. A majority of Americans support pro-life policies, more today than at any time since the Roe decision. More state laws have been enacted protecting unborn babies in the past decade than in the previous 30 years combined.

What happened? The pro-life community woke up and responded to a bad court ruling. Academics wrote the books and articles making the scientific and philosophical case for life. Statesmen like Henry Hyde, Edwin Meese, and Ronald Reagan crafted policy and used the bully pulpit to advance the culture of life. Activists and lawyers got together, formed coalitions, and devised effective strategies. They faithfully bore witness to the truth.

Three Strategies for Reviving Marriage

Everything the pro-life movement did needs to be done again, now on this new frontier of marriage. There are three lessons in particular to learn from the pro-life movement that I explore at length in “Truth Overruled”:

   1. We must call the court’s ruling in Obergefell v. Hodges what it is: judicial activism.

Just as the pro-life movement successfully rejected Roe v. Wade and exposed its lies about unborn life and about the U.S. Constitution, we must make it clear to our fellow citizens that Obergefell v. Hodges does not tell the truth about marriage or about our Constitution.

   2. We must protect our freedom to speak and live according to the truth.

The pro-life movement accomplished this on at least three fronts. First, it ensured that pro-life doctors, nurses, pharmacists, and hospitals would never have to perform abortions or dispense abortion-causing drugs. Second, it won the battle—through the Hyde Amendment—to prevent taxpayer money from paying for abortions. Third, it made sure government could not discriminate against pro-lifers and pro-life organizations.

Pro-marriage forces need to do the same: Ensure that we have freedom from government coercion to lead our lives, rear our children, and operate our businesses and charities in accord with our beliefs—the truth—about marriage. Likewise, we must ensure that government does not discriminate against citizens or organizations because of their belief that marriage is the union of husband and wife.

   3. We must redouble our efforts to make the case in the public square.

We have to bear witness to the truth in a winsome and compelling way. The pro-life movement accomplished this on different levels. Specialists in science, law, philosophy, and theology laid the foundations of the pro-life case with research and writing in their disciplines, while advocacy groups tirelessly appealed to the hearts of the American people. Pro-lifers did much more than preach, launching a multitude of initiatives to help mothers in crisis pregnancies make the right choice.

Now we must employ reason to make the case for the truth about marriage, communicate this truth to our neighbors, and embody this truth in our families and communities. Just as the pro-life movement discovered the effectiveness of ultrasound and letting women speak for themselves, the pro-marriage movement will, I predict, find the social science on marriage and parenting and voices of the victims of the sexual revolution to be particularly effective. Just as grassroots pregnancy centers exposed the lie that abortion is a compassionate response to unplanned pregnancy, we must show what a truly loving response is to same-sex attraction.

In “Truth Overruled,” I explain, in clear and sober terms, the enormous task before us of defending our families, churches, schools, and businesses from opponents who now wield coercive power in government, commerce, and academia. My goal is to equip everyone, not just the experts, to defend what most of us never imagined we’d have to defend: our rights of conscience, our religious liberty, and the basic building block of civilization—the human family, founded on the marital union of a man and a woman.

 - Ryan T. Anderson is the William E. Simon Senior Research Fellow at The Heritage Foundation and author of the just-released book, "Truth Overruled: The Future of Marriage and Religious Freedom," from which this essay is adapted.