By Mark Mardell
The floor of the community centre in Springdale, Arkansas, shakes to a staccato rhythm as the young Latino dancers practise their steps.
The young girls slip long dresses of fuchsia and aquamarine over T-shirts and shorts, swishing and swirling them in time to the beat. The teenage boys, solemn in concentration, join in, stepping and stamping, hands clasped behind their backs.
They are clearly having fun, but they and their parents are clear this is not just about keeping them amused. It is about nourishing their Mexican roots, making sure their culture doesn't shrivel and die in this corner of the Deep South.
I have come to Springdale because it is a harbinger of America's future. Ten years ago there were hardly any Latinos here - now they make up more than 30% of the population. Predictions suggest that by 2030, this is what the US will look like.
Right now, one in four Americans under 18 is Hispanic - that is, Spanish speakers with roots in Latin America. A lot has been written about the political impact of the growing Latino population, but I am interested in how it could change the culture, indeed the very nature, of the United States itself.
"The richness of our culture is not just music and dance, but who we are," Margarita Solorcano, the director of the dance project, tells me.
People ask when my relatives came across the border. I tell them, the border came across my ancestors”
"Living here, we have a lot to learn, but we also have a lot to teach, like the family unit, the sense of community, the loyalty to our traditions."
She says they have already altered attitudes in this very traditional and very white part of the world
"I feel it is changing - we are here, and everybody is learning from each other," she says.
"In the Deep South there are people who haven't had the experience of being around other types of people, so when they start mingling with different cultures, their attitudes change."
Of course, some parts of the US have always felt very Hispanic. Large swathes of the South-west were still part of Mexico until the mid-19th Century - just a heartbeat ago in historical terms.
As one young woman in Texas told me recently: "People ask when my relatives came across the border.
"I tell them, the border came across my ancestors."
What is different now is the huge growth in the Latino population far away from the border, sometimes in areas without a tradition of immigration from anywhere but Europe.
One of the dancers, Myra Rivas, suggests the growing Latino population defines one vision of what America should be.
"It will make a huge change," she says. "America is more than just America."
"Without Hispanics, without all these other cultures, it isn't really America. The US provides opportunities to every single culture there is and that's what makes America different."
When I ask what Latinos specifically bring to the US, she giggles and says: "The food! And our good looks!" The other dancers agree the food is pretty important.
While some Hispanics are wary of this stereotype, it is what many Americans think.
According to one survey around 80% think Latino culture has had a large influence on the US, and most say the biggest impact is on food and music.
It's true that tacos are as American as curry is British.
But perhaps Latinos add more than just a little spice to American life.
Growing a diocese
I go to Springdale's St Raphael's Catholic Church in search of a more profound answers. The airy church is framed by two large modern stained-glass windows. Father John Connell is saying Mass in Spanish.
It is one of three mid-week Masses in the language, which he learnt five years ago. After the service he tells me the increase in the Latino population has made a big difference, especially in his diocese, which covers the whole state.
"It has meant a huge change," Father Connell says. "We are pushing close to 200,000 Catholics in a diocese that used to have around 60,000.
"In the United States our Latino brothers and sisters are a blessing to the church. Without them the church would have been stagnant in numbers."
And he's sure it will grow still more.
"Almost every Latino woman in my parish is pregnant, so they are still in that mode of mother, family, father, three, four, five, six kids. So what's the impact? A huge explosion of Latino babies in the years ahead."
I ask him if a growth in Catholics means America will become more socially conservative. He's wary of that conclusion.
"I agree it may have some type of impact," he says. "Latinos come from predominantly Catholic countries, and their culture and religion are all wrapped up in one.
"We in the United States individualise everything - politics, religion, culture - it is all separate. Will it change? I don't know.
"The second generation will speak English, the third generation, they may not even speak Spanish and they may forget a lot of traditions and culture of their parents. That's the history of any immigrants to this country."
New immigrant waves
That's true. But this might be different for Latinos, for a couple of reasons. First of all, the Spanish language is already ubiquitous in the United States, and there are areas of the country where you need speak no English.
There are the big TV networks for a Spanish-speaking audience, Telemundo and Univision, as well as many newspapers and radio stations.
Many public notices, for instance on the buses I take in Washington DC, are all in English and Spanish.
Some schools are bilingual and those irritating automatic telephone options nearly always ask you to press one for English, two for Spanish.
All of this is constantly reinforced by new waves of Spanish-speaking immigrants who may have little English.
At Springdale Har-Ber High School, I sit in on a class for teenagers who are new to America. They are learning English through American history.
"What was the New Deal? Is it a he or a she? No it's an 'it'!"
The animated teacher, Jana McVay, engages the kids, putting her finger to her lips, acting out puzzlement, asking the kids questions.
She says it is important her pupils learn English.
"It's essential if they want to be successful," Ms McVay says. "I want my students to have the American Dream. I don't want my students to think they have to work in a factory.
"If they want to get a management job, go to university, they need to speak English."
But she doesn't think that means they have to lose Spanish, or their culture.
Perhaps becoming American no longer requires subscribing to a narrow vision of what that means.
"I have a friend who is a Latina and she can't speak a lick of Spanish - her parents subscribed to the idea that you come here and you become a Wasp," Ms McVay says.
"But that is changing and I think it will change the country. We talk to the kids here and they have an identity and they need not try to become someone else.
"They are aware that there is no box to fit into. The country is changing, it is becoming what it is, because of who they are."
Brenda and Carlos, two 16-year-old students from Mexico, can't imagine ever feeling American, but understand the lure.
Rick Schaeffer, communications director of Springdale public schools, says this corner of Arkansas is definitely a taste of what is around the corner for the country. And while some around here wouldn't agree, he thinks it is positive.
"America has always been a nation of immigrants, ever since the 1700s," Mr Schaeffer says.
"If you look at the Hispanic culture, they might be more like Americans used to be than Americans are today.
"They are family orientated. You don't see divorce. You sure don't see abortion. They are hard workers. They are industrious.
"In a way, they are a lot like the immigrants who came here in the 1700s, who built our great country into what it is today."
All those I spoke to were positive about what the increase in the Latino population would mean - although I didn't specifically seek out critics.
But I came away with a strong sense of one vision of America - that it is a project still in motion, and that the more it mirrors the world, rather than reflects a European identity that others have to squeeze into, the stronger it is.