When ‘who do you support?’ is a proxy for ‘who are you?’, the debate can be especially personal for football fans during the World Cup

Clad in an American national team jersey on the eve of the first US-less World Cup since 1986, Karla Cantu pondered who to follow this summer. So did other members of the Laredo chapter of the American Outlaws supporters’ group. They decided to allocate temporary loyalty via lottery. “We can’t come to a consensus. We’re going to do a draw,” she said.

Broadcasters have a commercial incentive to urge bereft Americans to watch Mexico in Russia and the demographic, cultural and geographic ties are obvious. But when “who do you support?” is a proxy for “who are you?”, the debate can be especially personal and complex – especially on a frontier that has become a playing field for nationalistic political games.

With sport’s inevitable twining of politics and patriotism, the World Cup can feel like the planet’s most divisive festival of unity even without the influence of a president who views everything as a rivalry match with only two possible outcomes: win or lose. It’s not an attitude shared by many who live at the border.

“We have a really interesting mix. We support the US as American Outlaws but we get a little bit of backlash from the Mexico fans because of our heritage, our culture,” said Cantu. “We try and make it a very, I guess, harmony-based environment where we can all thrive, US fans and Mexico fans, and live together in peace.”

Laredo is 95% Hispanic - the highest percentage of any large metropolitan area in the US. More than a quarter of residents are foreign-born. It is equidistant from the major Texas city of San Antonio, which has a solid second-tier football team, and Monterrey, home to two of Mexico’s biggest clubs.

Facing the Mexican city of Nuevo Laredo across the Rio Grande river, Laredo is a place of bridges and barriers. America’s biggest inland port thrums with trains and trucks but is a hub for a vast governmental apparatus of surveillance and separation. Crossing between countries is harder than it used to be. In football, though, Mexico come to you.

This time four years ago, the US’s World Cup publicity campaign was built around the slogan: “One Nation. One Team.” Yet, as well as working with the US Soccer Federation, Major League Soccer’s marketing arm, Soccer United Marketing, has long promoted Mexico’s American friendlies. They must be busy. Of the 220 Mexico fixtures from 2007 to the final tune-up against Denmark on 9 June, just over half took place in the US. Of those, 101 were friendlies, two-thirds of them in the US. Over that timespan, El Tri have appeared in 22 different US metropolitan areas. They have played 25 times in Texas and 27 times in California: combined, that is more games in two US states than in the whole of Mexico (46).

It makes sense: big stadiums, high ticket prices and a large and ravenous fanbase. There are an estimated 36 million Hispanic people of Mexican origin in the US.

Edith Ortiz, the Laredo Heat Soccer Club’s marketing manager, was born in Mexico City and has lived in the US for six years. The 33-year-old watched El Tri in San Antonio and Dallas. “It’s like if you were in Mexico,” she said. “In Mexico, soccer is everything for everybody.”

Growing the club scene in Laredo is more of a struggle. When the city found $20m for a sports arena a couple of years ago it built a baseball stadium. The Heat’s fourth-level amateurs play at a basic venue on the campus of Texas A&M International University.

On one searingly hot evening last month a few hundred fans perched on metal benches or lounged in the VIP section – a three-deep row of folding chairs along the sideline. Heat matches are a glimpse of an idealised American multicultural future; a youthful, hopeful, happy space that blends many nations into one, even as it splits one nation into many.

A 20ft-high inflatable Budweiser can loomed ludicrously behind one of the corner flags. The Mexico star, Javier “Chicharito” Hernández – in the guise of a life-size advertisement – stood beneath the bleachers: arms folded, face fierce, assuring you that El Tri mean business in Russia and advocating that you drink the Mexican football federation’s official beer.

The public address system faded out the otherwise incessant Spanish-language pop music and players lined up in the centre circle for the Star-Spangled Banner as everyone directed their gaze to the American flag behind one of the goals. Laredo, with players from 12 different countries in their squad, then thumped another Texas border club, FC Brownsville, 4-1.

The Heat’s owner, Shashi Vaswani, was born in India and lived in Hong Kong and Toronto before his family moved to Laredo in 1980. “[I] thought close to Mexico soccer’s got to be prevalent everywhere. Lo and behold there was no high school soccer, no club soccer, zero,” he said.

Vaswani, a 52-year-old hotelier and entrepreneur, wonders if the government’s anti-immigrant machinations will simply cement the region’s fidelity to Mexico. Longer term, though, he sees a generational shift. “I think it’s a 70-30 split here and it used to be 90-10, or 95-5, for Mexico,” he said. “The youth we’re right now trying to develop, there’s a 50-50 split. Fifty would say ‘look I’ll play for USA no doubt’, maybe 25 would say ‘I’ll think about it’ and 25 would say ‘I’ll probably play for Mexico’, but I think that’s going to evolve even more … Ten years from now I think you’ll see again a very different Laredo.”

As the Heat look to boost their English-language outreach, the US’s failure to reach Russia is a missed opportunity, Ortiz said. “We have been trying to grow the fanbase for the US since we’re on this side and this is kind of setting us back because now people just go for Mexico and that’s their first team; even if they’re US fans, some of them will go for Mexico. Other fans who haven’t decided, they will go for Mexico.”

Family tradition also matters, she added. “If they’re little they’ll root for Mexico because they don’t know [anything else]. The older ones will go for both. My daughter roots for both. I’m Mexican but my daughter was born here so she goes for both. And she has been taught to go for both countries.”

Rodrigo Marina, the Heat’s 24-year-old play-by-play commentator, was born in Mexico City and moved to Laredo when he was five. “When they play each other it’s hard, I’m a little torn, I’m a little divided. I love to root for Mexico and I love to cheer for the USA,” he said.

“I have a lot of friends who were born here, although they do have a heavy Hispanic background they do cheer for the USA; and I have friends that were born in Mexico, migrated to the USA and they just support Mexico to the fullest,” he said. “If they could unite, at least for 30 days, that would be great.”