Ukraine: Inside the Pennsylvania ammunition plant helping the war effort
Five thousand miles from the frontline battlefields, the bowels of a former railway plant in a Pennsylvanian city is an unlikely place to find Ukraine's war effort in full swing.
Sky News was invited inside a US Army ammunition plant for a tour designed to show that the West is not running out of ammunition.
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Last week, the NATO secretary-general delivered a blunt warning to Western nations.
"The current rate of Ukraine's ammunition expenditure is many times higher than our current rate of production," Jens Stoltenberg said.
And so on the production line of a century-old factory, in the rust-belt town of Scranton, American steelworkers are producing round after round of artillery.
We found an industry, increasingly dismissed as obsolete, now in overdrive.
"We're working as hard as we need to work to meet the requirements of the contracts," the US army's boss at this plant, Richard Hansen, told me as we watched red-hot steel rods pass down a conveyor belt.
"We're working two shifts every day - a solid two shifts every day, 15 to 16 hours a day, five to six days a week and also preparing to increase production incrementally."
None of the officials at the plant will mention Ukraine itself. Language is carefully controlled; instead the phrases are "matching contracts" and "meeting demand".
But the contract is Ukraine and the demand is huge. Officials admit that the production of artillery in America has not been this intense since the Korean War 70 years ago.
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Production is at a 70-year high
In this factory alone, 11,000 155 millimetre artillery rounds now roll off its line each month. And yet it is not nearly matching what Ukraine's army is using.
Between 5,000 and 7,000 artillery shells are used in Ukraine every day. In some of the most intense fighting, they've used 10,000 a day.
That rate is set to increase further as winter turns to spring and new offensives by both sides begin. It's why the US military is investing $2bn to ramp up production in facilities like Scranton.
Over the past several decades, Western military planners and political leaders have been shifting focus and investment to high-tech warfare.
'I am proud of what we do'
The conflicts in Iraq and Afghanistan were against insurgencies; asymmetrical battles where investment in equipment like drones became a priority over tanks and artillery.
Incorrect judgements were made about the likelihood of an old-fashioned mechanical war - a continental land battle.
Russia's invasion of Ukraine spooked western governments. China's eye on Taiwan further exposes western capability gaps and future challenges.
In America, Cold War-era factories and old rivalries are being fired up.
"Russia is obviously wrong and we are doing the right thing by supporting them," one worker told me.
Another added: "Yeah - it's a busy day right now. It's been going really good. I am proud of what we do. It's exciting to be a part of it."
Mr Hansen said: "It's an opportunity for local Scrantonians to be able to work for the US government and support the joint war fight so it's something that they appreciate."
The Ukraine conflict has proved that a "just in time" ammunition supply chain is unsustainable and stockpiles are shrinking.
But this race against Russia to rearm is time-consuming, expensive and the section of the production line we're watching in Scranton is the easy part.
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'We need investment'
From Pennsylvania, the artillery casings are transported a thousand miles west to Iowa where they are filled with explosives and armed with fuses. The raw materials for the explosives are costly.
From Iowa, they are then shipped to eastern Europe.
"It's a very difficult process, it's highly engineered, so certainly you don't wanna ramp up too quickly because quality is the number one aspect, what we look for. Nothing easier without being inspected multiple times," Mr Hansen tells me.
Russia is not constrained by Western industrial safety and quality standards.
It also has fewer commercial restraints. President Vladimir Putin has switched the Russian economy to a war footing allowing for increased production in an industry typically hampered by inefficiency and corruption.
In Pennsylvania, Mr Hansen welcomed the US government investment in his factory, but his message for the politicians and industrial leaders was clear.
He said: "You need to continue to invest your time and your money into a facility... we are communicating to our leadership, the things that we need here - me specifically at Scranton - need to ensure that we can continue to efficiently produce what we need to produce here."