The Dreadnought Class, the nuclear successor

Replacing a nuclear deterrent is a big deal, and  takes a long time. By 2016, the British government had already been working on the replacement for its Vanguard class SSBNs (Submersible Ship, Ballistic, Nuclear) for ten years. That year, Parliament voted to replace the Vanguard class, extending the Continuous At Sea Deterrent (CASD) beyond 2030 and initiating the Dreadnought class. A timeline of the key decisions and events is provided below: 

• 2006: Labour government releases a white paper, The Future of the United Kingdom’s Nuclear Deterrent, setting out its intent to renew the deterrent through the build of at least three new SSBNs to replace the Vanguard class. 
• 2007: Parliament votes on the general principle of whether the UK should retain a nuclear deterrent. Threats such as chemical and biological weapons were raised as alternative, more pressing matters, and hypersonics raised as an alternative to nuclear. 
• 2010: The Strategic Defence and Security Review defers Main Gate decision to 2016 and delivery of first in class to 2028 from 2024. 
• 2011: Initial Gate for the programme, meaning that an outline for the design of the submarine and indicative costs had been decided. Initial Gate led to a five-year assessment phase. 
• 2013: HM Treasury released additional funds, allowing long-lead items to be procured and to support infrastructure development at Barrow-in-Furness. 
• 2014: General Dynamics awarded contract modification to build 12 Common Missile Compartment (CMC) missile tubes for Successor Class. Design freeze for PWR3 Nuclear Steam Raising Plant. 
• 2015: Conservative government elected, with a manifesto commitment to maintaining CASD and procuring four Successor submarines. 
• 2016: Parliamentary vote commits to the Successor programme, 472 votes to 117. Construction of HMS Dreadnought initiated with steel cutting. 
• 2018: £960 million contract signed with BAE and Rolls-Royce (£900 million and £60 million respectively) for second stage of Dreadnought programme, allowing continued design and build of the first boat and start of the second. 
• 2019: Steel cutting ceremony for HMS Valiant. 
• 2020: Babcock contracted by General Dynamics to manufacture an additional 18 Missile Tube Assemblies for the CMC. 
• 2023: Thales awarded £193 million contract for optronic masts on the Dreadnought class. Steel cutting ceremony for HMS Warspite. 
• 2025: Keel laying ceremony for HMS Dreadnought and first sections observed moving to Devonshire Dock Hall. A model presented in parliament indicates an X-form rudder configuration. First steel cut for HMS King George VI.  

Delivery of the first of class, HMS Dreadnought, is expected in the early 2030s, and some progress has already been made towards completing that boat. The keel laying ceremony – a largely symbolic term for submarines – took place in March 2025. Three sections of the first of class have been observed in transit between the Central Yard production facility and the Devonshire Dock Hall at Barrow-in-Furness. Each submarine is built in 16 units, which are then assembled into mega-units for the aft, mid, and forward sections of each boat. The mega-units are then brought together to create a complete submarine. Steel has also been cut for HMS Warspite in February 2023, and HMS Valiant in September 2019, which suggests those builds are also progressing to some extent. However, for context, the steel cutting ceremony for HMS Dreadnought took place in October 2016, indicating that it might take as long as nine years to see real progress in production of the ships. The first element that was to be built in 2016 was the structural steel work for the ‘auxiliary machine space:’ according to the Navy, this contains switchboards and control panels for the reactor. Steel for the final Dreadnought Class, HMS King George VI took place on September 22, 2025 with King Charles present. 

The overall project, combined with the needs of the Astute class, has led to intensive investment in British manufacturing capabilities. There has been a factory and staff expansion at Rolls-Royce, as well as an extension to the facilities at Barrow-in-Furness. A £200 million Barrow Transformation Fund has been announced, which will provide £20 million a year for ten years to enable the expansion at Barrow-in-Furness. This covers basic elements such as new and improved housing in the area, transport improvements, and a social impact fund. The BAE shipyard employed 11,000 people in 2023, and had grown to 13,500 by the MoD’s annual report on its nuclear enterprise, with a projected demand of 16,500 staff by 2027. This is to say nothing of the Unity contract awarded to Rolls-Royce in 2025, which is valued at £9 billion, and will see the company support the production and delivery of all nuclear reactors in British service for the next eight years. The benefits to the British population and economy of the Dreadnought class are relatively clear, but what about the costs? 

The cost of deterrence

‘You could spend as much money as you can imagine for your entire life and never touch the sides of the cost of the deterrent,’ a civil servant once remarked to me. The costs are certainly huge, especially when the entirety of the Defence Nuclear Enterprise (DNE) is considered against the backdrop of difficulties across all three services with conventional capabilities. In 2023 all nuclear programmes and expenditure in the MoD were brought under one heading within the MoD’s budget: the DNE is a partnership between all organisations that support and deliver the UK’s nuclear deterrent. This includes the Defence Nuclear Organisation, Atomic Weapons Establishment, Strategic Command, Royal Navy, and Submarine Delivery Agency. BAE Systems, Babcock, and Rolls-Royce Submarines are also industry partners of the DNE. 

The funding comes from the MoD’s core equipment budget and is ringfenced, meaning that money cannot be taken to support other programmes. This is important for seeing the programme through to delivery, especially with changes in government. Decisions taken under the austerity drive led to reduced missile complements on the Vanguard class, for instance, and a lack of investment in the nuclear infrastructure needed to keep the Navy operating efficiently. 

The DNE accounts for around 18% of the MoD’s entire budget, with a total forecast budget over the next ten years of £130 billion, according to Madelain McTernan, the Chief of Defence Nuclear. The cost of the Dreadnought programme within that is immense, and the 2025 DNE update to parliament indicated a total likely cost to build the submarines of £41 billion, including a £10 billion contingency fund. By March 2024, £17.4 billion of the budget had been spent, with £3.37 billion of the contingency fund now committed. That estimate also includes some allowance for inflation over the course of the build phases. Nevertheless, the project is confidently expected to remain within its budget envelope – which is close to four times the estimated cost of the entire Astute programme. The annual in-service cost of the CASD has been estimated at 6% of the MoD’s annual budget prior to 2023 – which equated to around £6 billion per year, according to a research briefing from the House of Commons Library. 

Notably, these cost estimates are more than double what was originally expected when the Successor programme was initiated. The initial cost estimates made in 2006 for the entire programme – including the submarine build and investment in the Atomic Weapons Establishment – were between £15 and £20 billion, which included up to £14 billion for the submarines themselves. Cursory research indicates those amounts come to the current estimate of £31 billion when compound inflation is accounted for.

The Dreadnought Class, is it worth it?

 In a debate in Parliament in 2007, Foreign Secretary Margaret Becket said,

“We are talking about maintaining our ability to keep a minimum independent nuclear deterrent after 2024. To decide not to retain that ability would require us to be confident that, in the next 20 to 50 years, no country with a current nuclear capability would change its intentions towards us and that no power hostile to our vital national interests and in possession of nuclear weapons would emerge.”

At the time, North Korea and Iran were the primary concerns, and there appears to have been some lasting hope within the Labour Party at least, that nuclear disarmament would happen around the world. Unfortunately, Russia’s aggressive actions since, as well as North Korea’s further development of nuclear weapons, and China’s growing arsenal have proven Becket and the politicians who voted in support of what was then the Trident Successor Programme, right. The Dreadnought class now promises to replace the Vanguard class with the biggest and most advanced submarine the Royal Navy has ever put into service, but is the cost worth it? Well, there are two things to consider; nuclear blackmail, and America. 

American administrations have been pivoting towards the Indo-Pacific since George Bush was president. The Bush administration signalled a “shift” to Asia around 2006, leading to increased cooperation with Japan and India as well as efforts to increase the military capabilities of partners in the region. Obama formalised the policy in 2011 with the Indo-Pacific pivot, which was continued and accelerated under the following Trump and Biden administrations. This meant reducing commitments to the Middle East, Africa, and Europe to focus capabilities on deterring China in the Indo-Pacific. This context is important because America’s apparent withdrawal from the defence and security of Europe is sometimes portrayed as a quirk of the Trump administrations, but has actually been an enduring policy for more than a decade: all presidents since 2001 have called for Europe to increase its defence spending. So, with America pivoting away from Europe, it is critical that some European powers maintain a nuclear deterrent.

This is because without a nuclear capability, it would be possible for Russia to compel European nations to behave in a way that suits the Kremlin by holding the threat of its own nuclear weapons over them. This has been demonstrated, or at least attempted, throughout the Ukraine War, with Russia’s spokespeople and Putin frequently threatening nuclear use – especially against the UK. Whilst conventional capabilities are an important element of deterrence, they offer reduced benefits in the event that an adversary moves to deploy nuclear weapons. In this scenario, with Russia clearly comfortable to resort to nuclear threats and the US looking elsewhere, the primary nuclear capabilities providing any deterrence to Russia are British and French. Without them, it would arguably be difficult for Europe as a whole to properly deter Russian aggression, and it could even face attempts at nuclear coercion from rogue states like North Korea.

By Sam Cranny-Evans, published on September 30, 2025. This article was republished with a small update from the Calibre Defence magazine, which was distributed for the first time during DSEI 2025. If you would like a copy of the magazine, please contact us via admin@calibredefence.co.uk with your address and you will be added to the distribution list.

The lead image shows HMS Vengeance returning to HMNB Clyde, after completing Operational Sea Training in 2007. The Vanguard class has provided the UK’s CASD since 1993. Credit: POA Tam McDonald/© Crown copyright.