There is an old saying that history does not repeat itself, but it often rhymes.

That is why I have always been puzzled by how quickly people dismiss comparisons between modern immigration debates and the fall of Rome. The moment someone points out the parallels, the conversation is often shut down with accusations of fearmongering or political grandstanding.

History deserves better than that.

The Roman Empire was built in large part by absorbing outsiders. Rome granted citizenship, recruited soldiers from conquered territories, welcomed merchants, and incorporated people from every corner of the empire into Roman society. Some of Rome’s greatest generals, leaders, and even emperors were not born in Rome itself. Immigration and assimilation helped make Rome powerful.

The problem came later.

By the fourth and fifth centuries, Rome was no longer absorbing individuals and families into a confident and growing civilization. It was struggling to manage the movement of entire populations into an empire already weakened by political corruption, economic decline, military problems, and a loss of confidence in its institutions.

Was immigration solely responsible for the fall of Rome? Of course not.

But I believe it is equally dishonest to pretend that demographic change and cultural fragmentation played no role in the story.

The United States has faced similar questions before.

During the late nineteenth and early twentieth centuries, millions of immigrants arrived from Italy, Ireland, Poland, Germany, Russia, Greece, and Eastern Europe. My own Italian grandparents were part of that great wave of immigration.

Many Americans at the time feared these newcomers would never assimilate. Italians were considered too foreign. Catholics were accused of being loyal to Rome instead of Washington. Eastern Europeans were viewed as incompatible with American values.

History proved most of those fears wrong.

Within a few generations, those immigrants had learned English, served in our military, built businesses, raised families, and became Americans while still preserving parts of the cultures they left behind.

But there were important differences between then and now.

America in 1900 expected assimilation.

English was the language of schools, business, government, and public life. A child entering an American classroom learned in English. A worker entering an American factory worked in English. A family calling a business or government office did not hear, “Press one for English.” The message may not have been spoken out loud, but it was understood by everyone: if you came to America, you became part of America.

I believe we have moved away from that model.

Today we celebrate diversity, but often seem uncomfortable talking about assimilation. We encourage newcomers to preserve separate identities while paying less attention to the common culture that once bound Americans together regardless of where they came from.

What concerns me even more is the growing number of voices in public life that speak of America almost entirely in terms of its failures while dismissing its achievements and ideals. Every nation should be open to criticism, and America is no exception. But there is a difference between wanting to improve your country and teaching people that the country itself is unworthy of pride, loyalty, or gratitude.

At the same time, we increasingly see people identifying first by ethnicity, religion, politics, or ancestry and only second as Americans. A nation as diverse as ours can survive almost any difference if there remains a strong sense of shared identity holding it together.

For most of our history that common bond was not race or ancestry. It was a common language, a common civic culture, respect for the Constitution, and the belief that regardless of where our families came from, we were all part of the same American story.

At the same time, modern technology allows immigrants to remain more connected to their countries of origin than any previous generation in history. Immigration numbers remain historically high, while native-born Americans are having fewer children than previous generations.

The conclusions we draw from those trends are matters of opinion.

The trends themselves are not.

For me, the lesson of Rome is not that immigration destroys civilizations.

The lesson is that every civilization eventually reaches a point where it must decide whether newcomers will be integrated into an existing culture or whether the existing culture will gradually be transformed by the newcomers.

Rome faced that question.

Britain faces it today.

Much of Western Europe faces it today.

And the United States faces it today.

Recognizing those historical parallels does not make someone anti-immigrant or anti-American. If anything, it reflects a belief that American culture is something valuable enough to preserve and strong enough to pass on to future generations.

America’s greatest strength has never been race or ancestry.

Our strength has been our remarkable ability to take people from every corner of the world and turn them into Americans.

The question that concerns me is whether we still expect that transformation to happen.

Because history suggests that when assimilation weakens and cultural division grows stronger than national identity, nations eventually pay a price for it.

The people living in Rome never believed they were witnessing the end of Rome.

That is another lesson history teaches us.

The people living through history rarely know how the story ends.