Stephen Prothero is a professor of religion at Boston University and the author of “Why Liberals Win the Culture Wars (Even When They Lose Elections),” from which this essay is adapted.

For a time, it was fashionable to declare that America’s culture wars were over. “Culture wars issues not only had a very low profile in the [2008] campaign,” the Center for American Progress’s Ruy Teixeira wrote in 2013, “but, where conservatives did attempt to raise them, these issues did them little good. . . . There will be diminishing incentives for politicians to take up these causes for the very simple reason that they are losers.”

And yet here we are, in 2016, with the culture wars still going strong. Gun control, religious liberty, Black Lives Matter and funding for Planned Parenthood are all high-profile issues in the presidential campaign. Perhaps the most intense battle, though, is the one over immigration, which National Review’s Reihan Salam correctly identifies as a “fight over the future of American national identity in the face of rapid and accelerating demographic change.”

As a historian, I’m not optimistic that our culture wars will end anytime soon. These angry disputes about the meaning of America, and who is a true American, have been raging since the early days of our nation. We’ve lurched from one cultural conflict to the next. A loss in one battle further convinces culture warriors that our society is going to hell. So they cast about for another grievance — another “them” to blame for what is happening to “us.” In this way, the culture wars are perpetually rising from the dead.

As I investigated America’s culture wars from Jefferson to Obama, I found that they follow a predictable pattern. They tend to start on the right, with conservatives anxious about some cultural change. Yet conservatives almost always lose, because they lash themselves to lost causes. That’s how this latest round in our culture wars is likely to conclude, too. If you fear (as I do) what a President Trump might do, remember that the promise to build a Mexico-financed border wall or to ban Muslims from entering the country are as lost as causes can be.

Culture-war histories typically start with the 1960s. “The radical political mobilizations of the sixties — civil rights, Black and Chicano Power, feminism, gay liberation, the antiwar movement, the legal push for secularization — destabilized the America that millions knew,” Andrew Hartman writes in his book “A War for the Soul of America.” “It was only after the sixties that many, particularly conservatives, recognize the threat to their once great nation.”

But America’s culture wars go back much further than what conservatives sometimes call the “bad ’60s.”

Although early Americans were united in their hatred of the British and their love of George Washington, as soon as Washington retired from public service, they turned on one another in a series of disputes about the propriety of the French Revolution and the meanings and ends of their new nation.

Many of the attacks on the moral relativism of the ’60s reprised attacks on the multiculturalism of the Roaring Twenties. Many anti-Catholic tropes of the 1928 presidential election, in which a vote for Catholic Democrat Al Smith was said to be a vote for the Antichrist, were recycled from 19th-century smears of Catholic immigrants as shock troops for a foreign despot. Claims that President Obama is a closet Muslim are not novel, either. In the nasty election of 1800, now being staged in the Broadway hit “Hamilton,” Thomas Jefferson’s Federalist opponents accused him of believing in “the alcoran.”

In almost every case, these culture wars have been conservative projects, instigated and waged by people anxious about the loss of old orders and the emergence of new ones. Their anxiety finds expression first as a complaint about a particular policy, and second as a broader lament about how far the nation has fallen from its founding glory and how desperately we need to restore whatever is passing away. Or, to put it in Trumpian terms: The nation has been schlonged, but it will be great again.

Anti-Catholicism and anti-Mormonism were right-wing reactions to 19th-century Catholic immigration and Mormon migration, and to the moral, theological, social and economic threats those communities posed to Protestant power. Similarly, the culture wars of the 1920s and 1930s were conservative responses to the rise of the saloon and the speakeasy — and to the cultural pluralism brought on by rapid urbanization and immigration waves. In the contemporary culture wars, conservatives give voice to their anxieties about the loss of the traditional family and a homogeneous society. Cultural politics are always a politics of nostalgia, driven by those who are determined to return to what they remember (rightly or wrongly) as a better way of life.

Conservatives often blame liberals for the losses they are experiencing and for threatening the health and welfare of the nation. They say liberals started the culture wars by banning prayer from schools or agitating for feminism or black power. But conservative anxiety usually has little to do with liberal activism. It can be triggered by demographic trends. Or a Supreme Court ruling. Or a reality-television star.

To be sure, culture wars are battles between conservatives and liberals over conflicting cultural, moral and religious ideas. But at a deeper level, they are conservative dramas in which liberals are merely props. If liberals weren’t there, conservatives would have to invent them — and they often do.

Many people now view the culture of victimhood so visible on the right — in Bill O’Reilly’s war on the so-called “war on Christmas,” for example — as a pale imitation of the victimhood culture of left-wing identity politics. But this tradition goes back to Protestants who saw themselves as victims of Deism in 1800, of Catholicism in the 1830s and 1840s, and of Mormonism before and after the Civil War.

Even though conservatives tend to start the culture wars, liberals almost always win them. The “infidel” Jefferson and “papist” John Kennedy become president. Prohibition is repealed. Marijuana becomes legal. Gays and lesbians get marriage rights. Conservatives manage an occasional victory — on guns, for example. But in almost every arena where the contemporary culture wars have been fought, liberals now control the agenda.

Liberals may win our culture wars for philosophical reasons (because the constitutional principle of liberty is on their side) or for practical ones (because the nation is becoming more Catholic or more brown). But the most important reason they win is because their opponents fixate on lost causes. Conservatives instigated the Philadelphia “Bible wars” of 1844 when the Catholic population there was growing too quickly to remain on the margins. They attacked same-sex marriage most fiercely when attitudes toward gays were gravitating toward acceptance. “All conservatism begins with loss,” writes journalist Andrew Sullivan. When it comes to the culture wars, conservatism ends with loss, too.

What can these culture wars past tell us about the conflicts of 2016?

These, too, shall pass. The culture wars cycle may be eternal, but individual battles end.

To look at our culture wars over the long haul is to see not only how poisonous our politics can get but also how inclusive our nation has become. Conflicts give way to consensus. Causes once labeled “liberal” become “American values,” embraced by liberals and conservatives alike. Same-sex marriage becomes just marriage. Islam is recognized as part of our shared Abrahamic tradition. We cease to view particular immigrant groups as threats — as “drug dealers,” “rapists” and terrorists — and instead appreciate their contributions to our society.

Trump could still win the presidency. But electoral victories are often distinct from culture-war victories. Indeed, culture warriors often win by losing, as their gospel of salvation to the fallen and the lost yields enthusiasm on the campaign trail and votes on Election Day.

But no matter how this presidential election turns out, the arc of American history should continue to bend toward tolerance and inclusion.

Twitter: @sprothero

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