San Ysidro is the largest land border crossing in the Western Hemisphere.
On average, 70,000 vehicle passengers and 20,000 pedestrians cross north into the US from Tijuana, Mexico, every day.
About one third of the border, stretching from San Ysidro in California to Brownsville in Texas, is secured by a fence, wall or barrier.
The responsibility of enforcing the border falls largely to 16,500 border patrol agents.
National Border Patrol Council union representative Chris Harris took SBS on a tour inside the 45-kilometre “enforcement zone” where an estimated 30,000 “illegal aliens” were detained by border force agents last year.
“You’re kind of in a war zone here” Chris Harris told SBS US Election Correspondent Brett Mason.
“We’re pacifying it but it still is a war zone.
“The cartels are heavily armed and we are their enemy. They have some of the best equipment going.
“They have more money than we do.
“We know they have spotters watching us here right now. We’re playing cat and mouse but we’re underfunded, woefully underfunded.”
Mr Harris estimates that 60 per cent to 70 per cent of the agents’ arrests have criminal records “in the United States, Mexico or both”.
“If a guy comes here to better himself we feel that, we empathise with it.
“It’s the criminals we want to keep out, the terrorists, the people that want to do harm to our nation – but we get to decide.
“Every nation has the sovereign right to decide who comes into their country.”
In some sections, all that separates the two nations is a yellow line.
“Here you are standing in the United States of America. Three-foot over, you are standing in the United States of Mexico.
“There is no fence. There is no barrier. There is no wall.
“The only thing that prevents people from crossing in here is us.”
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The US Border Patrol is a minority-majority organisation and recently broke with tradition and endorsed Donald Trump for President.
“I understand why the National [Border Patrol] Council endorsed Donald Trump, I don’t have to agree.
“He acknowledged we are subject-matter experts and should have a seat at the table.”
Pointing out the tapestry of holes in the fence line – and large pile of handcrafted ladders seized by agents – Mr Harris acknowledged that a wall alone was not enough to secure America’s border.
“If you get that right mix of agents and technology and infrastructure, then you really can make a dent in securing the border.
“Let not make the mistake of thinking that because we can’t hermetically seal the border than it’s not worth doing – if we can’t build a fence that they won’t climb over, we shouldn’t do it.”
“We build fences around prison and people still escape.”
“We don’t stop building fences around prisons.”
Former San Diego Padres baseball star Enrique Morones made history when he became the first ever dual Mexican/American citizen.
He dreams of a day when there is no border wall at all and fears Donald Trump’s “hate words will lead to hate actions.”
“Had there been a wall along the entire 2,000 mile, 3,000 kilometres, on September 10, September 11 [2001] would’ve happened exactly the same way.
“Walls don’t stop people, they divert people.”
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In California, he believes those in search of a better life are being diverted in the desert to try and evade Border Agents and enter America.
His charity, Desert Angels, regularly leaves water in the desert in a bid to help save lives.
“Since that wall was built in October 1994, we estimate at least 11,000 people have died crossing or trying to cross into the United States.”
“We shouldn’t be building walls, we should be building bridges.”
Jannet Fernandez is one of the lucky ones.
She survived her illegal journey from Mexico to America in 2006.
She left behind her mother, father and brothers and sisters to give her children a better life.
“I don’t have my family – it is very painful.”
“Sometime I say to my children – this is the price I pay for you.”
Every Saturday Jannet takes her children Hector, 16, Jasmine, 14, and Yvette, 10, to Friendship Park, where border patrol agents allow families to talk through the heavy wire fence for four hours.
Jannet’s mother Rosario is waiting, and pokes her pinkie finger through the fence.
This is as close as they can get until Jannet’s residency application is decided – if she leaves America to visit her family in Mexico, she will not be allowed to return.
“Everybody talks about this country, America: ‘it’s the best, it’s the best’.
“But now I’m scared.”
“If Donald Trump wins, it’s not going to be the same United States.”
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