Image caption The abandoned factory, which made landline and coin-operated telephones, closed in 2000

Donald Trump says he would bring back outsourced manufacturing jobs from Mexico and China. There's a factory that is a symbol of outsourcing.

"You thought you had a job for life," says Gregg Trusty. "As long as you didn't show up to work drunk or punch your supervisor, you thought you could work there until you retired."

A wander around the factory Trusty is talking about gives a stark example of the precarious nature of the American economy today.

The gigantic Western Electric plant in Shreveport, Louisiana was once one of the country's biggest producers of telephones. Now it's abandoned, the machinery silently rusting. Nature creeps in on all sides. Dusty papers sit on desks and lights still blaze on to empty factory floors, as if the people working there were forced to leave in a hurry.

If you want to understand how Donald Trump has tapped into economic insecurity across America, this humid city of 200,000 in northern Louisiana is an excellent place to start. Western Electric was the wholly-owned manufacturing arm of corporate behemoth AT&T, which for most of the 20th Century held a monopoly on the US telephone business.

At its height, the company employed 7,500 people at its Shreveport plant. But long before the rise of Chinese competition, the ubiquity of the mobile phone and the North American Free Trade Agreement with Canada and Mexico - which Trump has called "worst trade deal ever" - the factory's future was clear.

Starting in the 1980s, AT&T slashed its domestic workforce and moved telephone manufacturing to Singapore.

"There was a feeling of disappointment," says Don Corliss, who worked at the plant for 25 years. "We moved from a manufacturing economy to a service economy.

"Did the average worker on the shop floor realise what was hitting them? I don't know."

Image caption Don Corliss worked at the plant for 25 years

Several factors led to the factory's closure. In 1984, a lawsuit ended AT&T's monopoly and opened up American telecommunications to competition. And, of course, the last 30 years have seen unprecedented international competition and technological change.

When Trusty moved here from the Midwest in the late 1960s he recalls that big celebrations would be held every time the plant added an additional 1,000 jobs, which in the early days happened every few years.

Later, as part of the company's public relations team, he would face the local media to announce round after round of layoffs.

"One time I was asked a question about how it made me feel," he says. "I told the reporter straight: 'We've lost some damn fine people today.'

"I meant it. It hurt, every time we did it. It was painful."

Image caption One of the coin operated phones manufactured by the Shreveport factory

After years of job losses, the plant, located in the Southern Hills area of Shreveport, closed for good in 2000. The fortunes of the workers themselves varied. Many retired, while others shifted gears with the aid of generous redundancy packages and company-funded education grants. Trusty worked in other jobs in public relations and journalism. Other former employees became small business owners, consultants, care home workers - and in one case, an elected state politician.

Randy Doss started on the factory floor and later became a supervisor. After he left the company in 1995, Doss ran a local transportation business with his wife before retiring earlier this year.

"We all had a sense of security. We thought we were fine," he says. "And we all bit the dust."

Despite that, Doss says he holds no ill will towards the company.

"It's a business decision pure and simple, and they could make phones cheaper elsewhere. That's business."

In Shreveport the absence of manufacturing jobs is palpable. Another iconic American company, General Motors, shut its local factory in 2012. That set off a wave of job losses at local suppliers, and today there's little heavy industry left.

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Harold Sater of the Southern Hills Business Association says the area around the AT&T plant suffered for years and despite rows of busy restaurants, petrol stations and other small businesses nearby, it doesn't quite compare to AT&T's heyday.

"The traffic you see now is just starting to come back to the levels back then," he says.

There were knock-on effects. Richard Corbett, the business association's current president, says crime increased in the area - a trend he saw first-hand in his day job as a local sheriff.

"It's simple. Fewer jobs nearby means fewer people came to the area to shop," Corbett says. "That led to problems and we're still working through them today."

Yet Shreveport does seem different from those Midwestern cities that were strangled by loss of their main industries.

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The economy here shifted and diversified. It's a regional centre for health care. Nearby oil and gas reserves have provided jobs, although that industry has gone through boom and bust. There's a large military base nearby and the city once had a thriving film industry lured in by tax breaks.

Meanwhile, casinos dotted along the Red River have led to a small revival downtown. The city's growth has slowed, but its population is stable - there's been no mass exodus.

Although most of the former AT&T site is abandoned, a couple of companies have moved in. One is even a small-scale manufacturer. Skyrunner is making futuristic recreational vehicles that can both drive and fly. The company is perfecting its designs and aims to ship its products around the world.

Image caption One of the vehicles that Skyrunner is making in one corner of the old AT&T site

What's missing is big industry of the kind that provides that elusive path for the low- and semi-skilled workers.

"We're still working on getting good-paying jobs for those people," says Sater. "There's almost nothing that pays $15 an hour outside of work on oil and gas fields. That's frustrating."

AT&T, meanwhile, no longer manufactures telephones in Singapore or anywhere else. It's a technology and media company. Its latest move is a bid to buy Time Warner, a proposal that both Democrats and Republicans are concerned about.

Among the firm's former employers in Shreveport, faith in Trump and his economic plan is decidedly mixed. Some, like Corliss, say they'll vote for him but only because they dislike Hillary Clinton more.

Doss is a staunch Trump supporter. He says he believes the Republican candidate when he says he can bring back manufacturing jobs to the US, even though he's thin on specifics. For Doss, like for many Trump supporters across the country, voting for Trump is a leap of faith.

"I don't know how he's going to do it," Doss says, "but I think that he can."

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