AMNA NAWAZ: The Trump administration's crackdown on immigration may be novel in its tools, methods, and scope, but, as Judy Woodruff reports for her series "Crossroads: America at 250," it belongs to a long tradition in this nation's past.

WOMAN: Our current course recalls the voyages of approximately 12 million American immigrants.

JUDY WOODRUFF: A mass of tourists huddled together on a ferry vying for a view of one of America's most iconic landmarks, the Statue of Liberty.

This statue is now seen as welcoming those from outside the country to the United States.

But it was not originally given for that reason.

NANCY FONER, Author, "Immigration: How the Past Shapes the Present: No, it was given by the French as a symbol of equality, having nothing to do with immigration.

JUDY WOODRUFF: Yet as millions of mostly European immigrants passed by it on their way to nearby Ellis Island in New York City Harbor, it became a symbol of their passage, of hope for a better life and of freedom.

NANCY FONER: It was the place where immigrants came.

MAN: Watch your step here.

Watch your step here, folks.

Please pay attention.

NANCY FONER: OK.

Thank you.

Thank you.

JUDY WOODRUFF: Disembarking on Ellis Island they were quickly processed, typically spending only hours here before heading into New York and beyond.

We hear a lot of conversation today about how my forebears came to this country.

They did it legally.

They went through the process of becoming a citizen.

In fact, it was much simpler than that in those days.

NANCY FONER: Well, there were no visas.

You didn't have to have a passport.

You could just come.

I mean, you had to get on the boat.

At Ellis Island, only 2 percent of the immigrants who went through were denied entry.

JUDY WOODRUFF: Only 2 percent?

NANCY FONER: Only 2 percent.

And there were no numerical limits on immigration.

JUDY WOODRUFF: My guide was Nancy Foner, a sociologist who has spent her career studying and writing about waves of immigrants, how they changed over time, and how, in turn, they changed this country.

NANCY FONER: The history of the United States is in good part a history of immigration, of people coming here to make a better life for themselves and their families, in some cases to flee persecution, so that immigration is really in the lifeblood of America.

But every time we have had massive waves of immigration in the United States, there's also been a negative reaction among some parts of the population, a hostility to immigrants, a worry that they're not going to fit in, that they're changing America for the worse.

JUDY WOODRUFF: In her new book, "Immigration: How the Past Shapes the Present," she explores the parallels and differences she sees between our history and today, including the many nativist movements, the Know-Nothing Party of the 1840s and '50s, a Protestant response to waves of Irish Catholics and Germans that sought to impose a 21-year waiting period for naturalization, up from five years.

The Chinese Exclusion Act later that century that prevented Chinese laborers from becoming citizens for 10 years, the door slamming shut in 1924, after millions of Southern and Eastern Europeans, including Jews and Italians, arrived at the turn of the century, and multiple efforts to deport Mexicans in the 20th century, including Operation Wetback in 1954.

NANCY FONER: On a more positive light, immigrants have built America, and they have rebuilt America throughout American history.

ANNIE POLLAND, President, Tenement Museum: So we are in the Baldizzi family apartment.

JUDY WOODRUFF: After departing Ellis Island, some ended up here in the cramped apartments of Manhattan, where they lived and worked, now memorialized at the Tenement Museum.

ANNIE POLLAND: So, Adolpho put up FDR.

And Rosaria said he couldn't be higher than the saints.

JUDY WOODRUFF: Oh.

(LAUGHTER) JUDY WOODRUFF: Annie Polland is the museum's president.

She showed me around a unit once occupied by an Italian family, the Baldizzis, with Russian Jews next door.

Germans, Irish, and Chinese also called this building home.

ANNIE POLLAND: The stories of how people got by have always fascinated me.

What was it like to come from another country?

These are people who chose to come here because they could embrace the ideals of this country and what the founding fathers had envisioned.

JUDY WOODRUFF: It's estimated that 40 percent of Americans today can trace their heritage back to Ellis Island.

Yet, in 1924, responding to that wave of immigration, President Calvin Coolidge signed the Johnson-Reed Act into law, slamming the door shut to millions more for decades to come.

The term MAGA, Make America Great Again, is seen as referring, we think, to the 1950s, a time when -- of relative peace in the country, the economy seemed to be booming, we were growing as an industrial powerhouse.

And that's pointed to as an ideal time.

What was the state of immigration?

NANCY FONER: Very, very low, because, in 1924, there was a very, very restrictive immigration bill that passed in Congress that created national origins quotas, and that these national origins quotas were set up to favor and did favor Northern and Western Europeans.

JUDY WOODRUFF: Foner says, over time, many Americans came to adopt myths about those ancestors and how quickly they assimilated.

NANCY FONER: People say, well, but my relatives when they came, they learned English right away.

Well, they didn't learn English right away.

What we see is, the three-generation model of linguistic assimilation still holds today, as it did in the past.

JUDY WOODRUFF: Another common myth, that first-generation immigrants through hard work quickly moved up the economic ladder.

NANCY FONER: Well, it wasn't so quick.

What studies show is that immigrants who came -- this is the foreign-born, they were born abroad -- came and that they made incremental, small steps up the ladder.

And so there are these many myths that are important, because they set up these immigrant heroes and heroines who were somehow superior, did things the right way, moved ahead, became American right away.

And against that, it's very hard to compete, because that didn't happen.

JUDY WOODRUFF: In 1965, amid the civil rights movement, a women's rights movement, and the expansion of federal programs known as the Great Society, President Lyndon Johnson signed the Hart-Celler Act at Liberty Island, a law that replaced those strict quotas with a system favoring family-based reunification and skilled labor.

LYNDON JOHNSON, Former President of the United States: Now, under the monument which has welcomed so many to our shores, the American nation returns to the finest of its traditions today.

JUDY WOODRUFF: Some lawmakers at the time thought that would preserve the overwhelmingly white and European migration pattern.

But, over time, it led to far more migration from Asia, Africa, and Latin America, and a diminishing white majority.

The percentage of foreign born in the U.S.

today is nearly 15 percent, near the all-time high in 1890.

NANCY FONER: What's different today is, the absolute numbers are much higher.

So there are about 50 million immigrants in the United States today.

And if you add on their children, there are 100 million, which is 29 percent of the population.

So that's immigrants and their children, OK?

JUDY WOODRUFF: What do you think is the relationship between that, those numbers, and what's happening right now?

NANCY FONER: Well, I think the numbers are causing fear, I guess, among some Americans, and exacerbated by the fact of the economic situation in the United States.

And it's especially riled up by politicians, who make the most of that.

Instead of saying, well, the problem is that they're outsourcing jobs, or that we have tremendous economic inequality in the nation and that Congress isn't doing enough to change this, people feel, well, immigrants are causing it.

DONALD TRUMP, President of the United States: They come from Africa.

They come from Asia.

They come from South America, but not just South America.

They're all over the world.

They dump them on the border and they pour into our country.

JUDY WOODRUFF: Like many before him, President Trump built his political career on these myths and distortions about immigration, pledging to build a wall and to deport millions of undocumented people, who represent about a quarter of the total immigrant population.

DONALD TRUMP: They're ruining our country, and it's true.

They're destroying the blood of our country.

That's what they're doing.

JUDY WOODRUFF: He renewed his pledge in 2024.

And, while in office, his administration has vastly expanded Immigration and Customs Enforcement, detained and deported hundreds of thousands of people, and faced backlashes over the killing of American citizens and those in custody.

NANCY FONER: We are a nation of immigrants, and immigration has been tied into our history for so long.

So, to see this rejection of immigrants, this victimization of immigrants is very, very concerning.

JUDY WOODRUFF: Heading into the midterms, our recent PBS News/NPR/Marist poll shows that voters' preference for Republicans on the issue of immigration has disappeared since 2024.

But with a closely divided country and a potentially divided Congress and government, it's unclear what legislative fix might be on the table, whatever the realities on the ground.

Population-wise, we're heading into a period where the birth rate is going down.

The Baby Boomers are retiring.

They're going to disappear.

How do you see immigration fitting into the American story going forward?

NANCY FONER: I think there's going to be a need for workers.

Plus, with this aging of the population, many Americans are going to need care.

And who is going to care for them?

Because in -- the caregiving jobs in this country are overwhelmingly immigrants.

And who is going to pay into Social Security to pay for retirees and medical needs of the elderly?

The demographic and economic pressures should lead to at least continued large, high numbers of legal immigration.

JUDY WOODRUFF: A prediction that this country will continue to rely on immigrants, but whether it welcomes them is another story.

For the "PBS News Hour," I'm Judy Woodruff in New York Harbor.