'You've got Russia and NK to think about' - the view from Britain's nuclear war town

Helensburgh on Scotland's west coast is home to the UK's nuclear weapons - but do the people living there want them?

In the late afternoon sun, you wouldn't know that the deep waters are home to Britain's four nuclear-armed submarines.

These weapons of mass destruction - Trident - are designed so that one of them is always out at sea, poised to fire a nuclear warhead at an enemy.

Since 1969, an armed British submarine has always been on patrol.

'Cutting about'

The submarines slide silently back and forth between open waters and the inshore Navy base at nearby Faslane, where they are kept and maintained.

"They're so close to you," says 18-year-old Kristen Polley.

"You drive past them. You see them just cutting about in the water. It's mental.

"If you're about at night-time, you can see them transporting stuff in and out of the base."

Kristen's friend Amber Collins, also 18, adds: "I don't think it's right. I don't think it's morally OK."

Kristen and Amber are with two other friends who don't want to be identified.

Like many people around Helensburgh, they have close relatives that work on the Trident base.

Kristen and Amber aren't big fans of the Trident base

However, all four friends say they would rather the base didn't exist.

"I don't think we should be putting money into things like that," Amber adds.

'You've got the Russians, haven't you?'

Later we meet Graham, walking a red-haired terrier. He doesn't stop long, but says his dog's called Tyrion.

As in Lannister?

"Yes - because he's small, and ginger."

What does Graham think about Trident?

"You've got the Russians, haven't you, and North Korea," he says.

"So I think we should have it as a deterrent - and it creates jobs as well."

So between them, Graham, Kristen, and Amber sum up some of the main arguments in the long-running political debate around Trident.

Do we need it to keep the UK safe - and to guard against nuclear attack from other countries?

Is it morally right for Britain to keep and threaten to use such devastating weapons?

Is maintaining Trident the best use of the billions of pounds it costs taxpayers every year, when schools and hospitals could use more money?

This children's climbing frame is next to the Trident base at Faslane

Do we need it to keep the UK safe - and to guard against nuclear attack from other countries?

Is it morally right for Britain to keep and threaten to use such devastating weapons?

Is maintaining Trident the best use of the billions of pounds it costs taxpayers every year, when schools and hospitals could use more money?

Where do the political parties stand on the issue?

The Conservatives, UKIP and Northern Irish Unionist parties would all keep and renew Trident. So would Labour, though they also say they'd work for a "nuclear-free world".

The Liberal Democrats would reduce the number of submarines from four to three and no longer promise to always be ready to fire. They say enemies thinking you might be ready at any given time is deterrent enough.

The SNP, the Greens, Plaid Cymru, and the Northern Irish parties Alliance, Sinn Fein and the SDLP all want Trident closed and the billions of pounds saved to be spent instead on other public services.

Mutually-assured destruction

The idea of Trident is that other countries will be put off launching a nuclear attack on Britain, because they know they'll face the same or worse themselves in retaliation.

The concept is known as mutually assured destruction (MAD for short).

Each of the submarines can carry up to 16 Trident missiles, but usually only carry eight. Each of these can be fitted with different warheads.

The subs also carry a sealed "letter of last resort" written by the prime minister of the day, setting out instructions to follow if the UK has been devastated and the government destroyed.

Anthony used to work on the nuclear subs

On Helensburgh's waterfront, we also meet 28-year-old Anthony Robson, who says he was an engineer on the nuclear subs for several years.

'Is it an ideal world? It's not'

"It's something that I hope is never going to have to be used," he says. "But the reason it's never going to have to be used is that it's there.

"Hopefully in ten years time they will reach a point where we don't need Trident - in an ideal world. But is it an ideal world? It's not.

"And certainly, if you took it away from round here, this area would be a ghost town."

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