The 33-year-old at the forefront of Britain’s defence revolution

To see the future of Britain’s defence industry, you have to visit a four-storey building found on what used to be a car park off Old Kent Road. This clean and functional edifice is the biggest new factory in London since the Second World War . A Union Flag overlooks the factory floor , where 12 machines are silently engaged in turning steel, aluminium and titanium into precision components for jet engines, drones , robots and much more.

Presiding over them is Alexander Fitzgerald, the 33-year-old founder and chief executive of the company, Isembard, which he established in late 2024. Like everyone who creates a successful business, the T-shirt-wearing entrepreneur spotted a problem and proposed a solution. “What’s happening across every single sector right now – from aerospace to defence to robotics to energy to semiconductors – is that demand is massively increasing, but the supply of manufacturing capacity to make those components is reducing,” he says.

Isembard’s driving purpose is to provide some of that desperately needed extra capacity. The opportunity is all the greater because of a revolution sweeping Britain’s defence industry. For generations, the sector has been dominated by a handful of large “prime contractors”, such as BAE Systems, which specialise in the slow and hugely expensive production of a relative handful of advanced jet fighters, tanks and warships, designed to stay in service for decades.

But the lesson from Ukraine is that there are increasing – and critical – advantages for countries that can speedily produce an abundance of smaller and cheaper systems, such as drones, then constantly improve and redesign them, and turn out new and better models every few months. This requires a multitude of small and medium-sized enterprises that can compete to be the most innovative and efficient by deploying AI to make an ever-changing array of components as quickly and cheaply as possible.

Isembard is already doing exactly that. Companies send 3D designs for the parts they need, and Isembard manufactures them according to those designs. “We build our own software and AI to make setting up our factories and running our factories really efficient,” says Fitzgerald. At present, about 95 per cent of components for manufacturing are produced by small and medium-scale businesses. It is an extraordinary fact that the average age of the owners of these companies in the UK is 65 – and that no less than 40 per cent of them plan to retire within five years.

At the exact moment when Europe is rearming – with all Nato countries, including Britain, pledging to spend at least 3.5 per cent of GDP on defence by 2035 – the supply chain for new components is contracting. Hence, Isembard is expanding rapidly to meet pent-up demand. Fitzgerald opened his first factory last year, and today his company has 18 worldwide – eight in Britain, eight in America and one each in France and Germany. This growth has been accelerated by Isembard’s unique business model, which allows for franchised factories.

All but five of the existing plants are not owned by the company, but franchised to individual operators. The newest, in Swindon, took a mere 90 days to set up, and Fitzgerald aims to get this down to one or two weeks. Speed and agility are everything. Fitzgerald notes that what has allowed Ukraine to resist the Russian invaders is not one kind of exquisitely engineered drone, but rather a vast and constantly changing array of different models.

“In Ukraine, it’s not one type of drone – and 10 billion of them,” he says. “It’s a zoo of different types of drones, at all classes and all stages. Then you need to be able to scale up.” Fitzgerald adds: “You need a manufacturing base, which is fundamentally a question of, ‘Have you got enough stuff that can make stuff? Have you networked them enough to be more efficient?’ That’s really the core of our business.” Reindustrialising Britain by reshoring production is, he believes, the key to the country’s future prosperity.

“The grand theory of everything is manufacturing because it’s the root of our prosperity, security and purpose,” he says. “I subscribe to the manufacturing dream – that means security and prosperity [depend on] your ability to make stuff.” Nearby, the computer numerical control (CNC) machines – which have affectionate nicknames such as Cathy and Big Bertha – on the factory floor are playing their part in reindustrialising Britain by turning out the precisely shaped objects that will soon be flying at high speed as the components of jet engines or drones.

The factory, which covers three floors and 160,000 square feet, aims to triple its workforce to 200 by the end of next year. Taking delivery of the hulking CNCs required Fitzgerald to install a bigger loading door in the building, which was previously used as a grocery depot. The machines had to arrive in the early hours of the morning, since there are timing restrictions within three miles of Charing Cross for loads of that weight and size.

Fitzgerald emphasises that Isembard is not a “defence tech company”, but rather a “manufacturing company”. About 60 per cent of its customers are in aerospace and defence, while most of the rest are in robotics. But Russia is unlikely to be interested in that distinction as its intelligence services carry out their escalating campaign of sabotage and subversion across Europe, including in Britain. Is Fitzgerald concerned about that threat?

“Yes, and I think the Government should be concerned,” he replies. “We have good security protections in both the cyber and the physical side. We’ve had a lot of support from the Government, and from the police and other agencies, as well.” Fitzgerald has personal experience of Whitehall, since he spent three years as a Treasury civil servant after graduating from Nottingham University with a degree in biochemistry. Earlier, he had also tried his hand at journalism as an intern at City AM .

He enjoyed his time working in the Government, but cannot help remembering: “When I thought I had the right answer for something, it still had to go through six pairs of hands to get to someone to make a decision. That frustrated me.” He left the Treasury to start a broadband company that amassed almost 100,000 customers before he sold it to Octopus Group in 2022. Fitzgerald founded Isembard soon afterwards, and the company now makes components for customers like Anduril, which manufactures drones and autonomous weaponry, and Oxford Space Systems, which produces the antennae for satellites.

In the past, certain British investors and banks had a fastidious disdain for any businesses linked to defence, some of which were denied financial services. Fitzgerald, who is also an Army reservist, has encountered no such difficulties, and he believes that attitudes have changed. “I think Ukraine has changed that,” he says. “Geopolitics has changed that.” Something else that has changed is the attitude towards manufacturing in general.

One of Andy Burnham’s central priorities is “reindustrialisation” and recapturing the dynamism of former years. In that spirit, Fitzgerald named his company after the great Victorian engineer, Isambard Kingdom Brunel, though he adapted the spelling of his hero’s Christian name because the original domain had already been taken. Today, he keeps a black top hat on his desk in tribute to the man whose individual drive and genius powered Britain’s first industrial revolution.

His other inspiration is Lord Beaverbrook, the minister for aircraft production in 1940, who galvanised British industry into delivering 100 Spitfires and Hurricanes every week, making him an architect of victory in the Battle of Britain and changing the course of the Second World War. “The Air Ministry didn’t like him. He was threatening to resign the whole time, but he got the job done,” says Fitzgerald, who notes that Beaverbrook tripled production in a matter of months by distributing the manufacture of Spitfire and Hurricane components between hundreds of superbly innovative and cost-efficient small and medium enterprises across the country.

That formula saved Britain in 1940. It might yet do the same again.