Mothers carrying their children smile, give me a thumbs up, and then point to a riverbank fifty metres or so away.
We’re on a walkway bridge between the Mexican city of Matamoros and Brownsville in Texas. The riverbank is of course the United States – so close you feel you can almost touch it.
For these families wide-eyed with excitement, this is the moment they’ve dreamt of. Many have endured months, even years, on the road.
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Sometimes travelling thousands of miles through hostile countries, outwitting cartel gangs, and managing dizzyingly contradictory bureaucracy, all to get to this point: an asylum interview with United States border officials, and almost certain entry.
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On its face, this all sounds like a system working in perfect harmony with the needy being helped by a welcoming country.
But in reality, migration is a hotly disputed issue that is likely to dominate the Trump-Harris debate, and the run up to the presidential election itself.
You can watch live coverage of the debate between Kamala Harris and Donald Trump from midnight tonight on Sky News, on web and on mobile
The group I am with on the bridge is mostly from Cuba, Nicaragua, Haiti, and Venezuela.
They’re claiming asylum, and with their paperwork and appointment email in hand, they approach the border with some trepidation but mostly with excitement and joy.
Many have waited months for their appointment to come through after applying for asylum on the US Customs and Border Protection (CBP) app.
This group of a few hundred people on the bridge are now just a few steps from America.
As they shuffle forward, CBP guards check their papers, make sure there are no errors, and wave them through to the other side for their case interviews.
These families, these children, are about to start a new life.
Along the border here in Matamoros, there’s little sign of Donald Trump’s border wall, but he’d doubtless approve of the razor wire fortifications on the American side of the Rio Grande.
Experts here say there’s no doubt who those seeking asylum are backing in this election and this debate – and that’s Kamala Harris, who is seen to have a far less hostile approach to immigration.
“I think the best would be a flexible US immigration policy again, like President Biden’s when he began his administration,” Oscar Misael Hernandez-Hernandez said as we chatted alongside the dozens of cars and trucks crossing the border.
A professor of social anthropology at the El Colegio de la Frontera Norte research centre and an expert on Mexico-US border issues, he added: “Biden broke with ultra-conservative vision and immigration policy.
“So, I think if Harris implements a migration policy like this if she wins the presidency of the United States, it would be not only quite good for migrants in terms of human rights, but also quite good for international diplomacy, because the relations of the United States, at least with President Trump, if he wins, would be quite disastrous as they were in the past.”
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In shelters and hostels across Mexico, many other migrant families simply have to wait for their border appointments.
It’s like a lottery, and it can take a long time for their number to come up.
Few leave the shelter; they would be easy prey for cartel gangs who would kidnap and hold them for ransom.
Marlen Cabrera, 39, from Honduras, and her family are waiting it out along with 200 others at the Casa del Migrante San Francisco de Asis shelter.
Any tightening of the immigration rules – as threatened by Donald Trump – would be a disaster for her.
I asked her what she would do if the laws changed with a Trump victory. She says she doesn’t like to think about what-ifs.
“I’ve been here so long, and not being able to get in would be hard because it’s the only option I have,” she said.
“I have to get in. It would be really terrible if we couldn’t. And I don’t just speak for myself, I speak for everyone here.”
Jose Valdivia, the Nicaraguan manager of the shelter is even clearer.
“Everybody, since the last election, we all wanted the Democrats to win, right? Because the Democrats look out for the little guy,” he told me.
“That’s what everybody here as a migrant wants, we want the Democrats to win. No one wants Trump.”
Day in, day out, in any weather, the migrants line up for their appointment here at the border in Matamoros.
Along the almost 2,000-mile-long border separating Mexico and the United States, thousands of applicants are screened every day and allowed to enter America legally to start new lives in their new home country.
But these migrants are at the centre of one of the most divisive issues in America right now.
Since the summer, border restrictions introduced by the Biden administration, combined with assistance from Mexican authorities who hamper the movement of migrants to the border, has brought about a large reduction in the number of people illegally entering America.
Despite this, President Biden is widely considered to have failed on immigration, and while Kamala Harris’s team have been working hard to cast her as a sort of new candidate and a breath of fresh air, she is – whether they like it or not – part of this administration and is tainted by its perceived failures.
The latest polls suggest Donald Trump scores well on the immigration issue, and his team have been releasing pointed “attack ads” on Kamala Harris and her team on this subject. They in turn have released adverts attacking Trump.
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You can watch live coverage of the debate between Kamala Harris and Donald Trump from midnight tonight on Sky News, on web and on mobile
In the debate itself, Trump is widely expected to try to nail Harris on immigration, and she will have to find a way to counter that.
Undoubtedly, she will point out that Trump’s supporters kiboshed a cross-party action plan for migration, but she is still tainted for certain.
While this will all play out in the political rough and tumble of the electoral process, it is important not to forget that thousands upon thousands of people will be affected by America’s future stance on immigration.
And for some asylum seekers, it is quite literally a matter of life and death.