Dismantle nuclear weapons and cancel Trident
Green · what the evidence says
An independent, source-checked look at Green’s policy “Dismantle nuclear weapons and cancel Trident” — what it would actually do across the things that affect your life. Every claim below quotes the source behind it. How this works.
Public finances & the next generation — Helps
moderate · moderate confidence
Cancelling Trident and its replacement would avoid tens of billions in future committed spending, freeing fiscal headroom over the long run. The main caveat is that decommissioning costs are unquantified and could offset a meaningful share of the savings.
The evidence
- The policy commits to cancelling the Trident programme and dismantling nuclear weapons. — greenparty.org.uk (manifesto) — “cancel the Trident programme”
- The Dreadnought submarine replacement programme is estimated to cost £31bn for design and manufacture plus £10bn contingency, totalling up to £41bn. — researchbriefings.files.parliament.uk (government) — “estimated to cost £31 billion for design and manufacture, with an additional £10 billion contingency, bringing the total acquisition cost to an upper estimate of £41 billion”
- A further £15bn has been allocated within the current Parliament for the nuclear warhead replacement programme. — commonslibrary.parliament.uk (government) — “The programme to replace the UK's nuclear warhead has an allocated £15 billion within the current Parliament (to 2029)”
- Annual operating and maintenance costs for the existing system are approximately £3bn, around 6% of the defence budget. — en.wikipedia.org (media) — “Its annual operating and maintenance costs are estimated at £3 billion, or about 6% of the defence budget in 2022/23”
- Overall Defence Nuclear Enterprise spending was ~£9.4bn in 2023-24 and is projected to rise to 20–25% of the MoD's overall budget. — vertexaisearch.cloud.google.com (media) — “Defence Nuclear Enterprise (DNE) spending was around £9.4 billion in 2023-24 (0.3% of GDP), accounting for roughly half of the UK's equipment spending, and is projected to rise to between 20-25% of the Ministry of Defenc…”
- Short-term savings from cancellation could be partially offset by significant but unquantified decommissioning costs. — theguardian.com (media) — “short-term savings from cancelling the existing Trident system might be offset by significant decommissioning costs”
- Precise costings for cancellation are difficult because the MoD does not publicly plan for such a policy. — theguardian.com (media) — “The Ministry of Defence does not publicly plan for such a policy, making precise costings difficult”
Biggest unknown: The scale of decommissioning costs for existing submarines, warheads and infrastructure is uncosted — the MoD does not publicly plan for cancellation, making net savings genuinely uncertain.
Our reading: Cancelling Trident has a clear, large positive effect on O12 in the long term. The committed pipeline of spending is substantial: up to £41bn for Dreadnought acquisition, £15bn for warhead replacement within this Parliament alone, and roughly £3bn per year in ongoing operating costs — all of which would be avoided. The Defence Nuclear Enterprise's share of the MoD budget is also projected to grow significantly, so the trajectory of avoided spending is upward. On the O12 rubric, this represents avoided borrowing or taxation to finance what is primarily a consumption/security expenditure rather than productive investment that raises future economic capacity. The direction is therefore 'improves'. Magnitude is scored moderate rather than major because: (a) decommissioning costs are real but unquantified and could absorb a meaningful share of near-term savings; (b) the MoD has no public costing for this scenario, introducing genuine uncertainty; and (c) some savings would only materialise over a multi-decade horizon. The long-term time horizon reflects that the bulk of the Dreadnought and warhead programme costs fall over the 2020s–2040s. Confidence is moderate: the gross savings are well-evidenced from parliamentary sources, but the net fiscal position depends critically on decommissioning costs that no authoritative source quantifies. Advocacy-source lifetime cost estimates (E6, E7 from CND) have been noted but not used to drive magnitude, consistent with symmetric treatment of advocacy sources.
Good work & fair pay — Hurts
moderate · moderate confidence
Cancelling Trident would directly eliminate tens of thousands of well-paid, specialist jobs — mostly in specific regions — with no guaranteed replacement. Advocates argue diversification could offset this, but no funded, binding mechanism exists in the policy.
The evidence
- The policy proposes to cancel the Trident programme. — greenparty.org.uk (manifesto) — “cancel the Trident programme”
- The Defence Nuclear Enterprise currently supports around 47,600 jobs, expected to rise to 65,000 by 2030. — gov.uk (media) — “The Defence Nuclear Enterprise (DNE) currently supports an estimated 47,600 jobs across the UK, with an anticipated increase to 65,000 by 2030”
- Average salaries in the defence nuclear industry are around £45,500 — 20% above the national average. — gov.uk (media) — “Average salaries in the defence nuclear industry are higher than the UK average, at £45,500 – 20% above the national average”
- The Dreadnought programme alone is expected to support over 30,000 UK jobs at its peak. — gov.uk (media) — “The Dreadnought programme alone is expected to support over 30,000 UK jobs at its peak”
- Cancellation would cause substantial job losses, particularly in Barrow-in-Furness and other nuclear supply-chain regions. — gov.uk (media) — “Cancelling the programme would therefore lead to substantial job losses, particularly in areas like Barrow-in-Furness, where the submarines are built, and other regions heavily invested in the nuclear supply chain”
- CND estimates around 11,520 civilian jobs are directly dependent on Trident and argues savings could fund investment in other sectors to create more jobs. — cnduk.org (media) — “CND, which estimates approximately 11,520 civilian jobs are directly dependent on Trident, argues that the money saved could be used for "massive investment" in other sectors to create more and better-paid jobs”
- Advocates suggest a Defence Diversification Agency could transfer skills to conventional shipbuilding, renewable energy, and engineering. — pnnd.org (media) — “They suggest establishing a Defence Diversification Agency to transfer skills to industries like conventional shipbuilding, renewable energy, electronics, and engineering”
- The TUC advocates protecting good-quality jobs in defence communities through diversification plans. — pnnd.org (media) — “The Trades Union Congress (TUC) also advocates for protecting and prioritising good quality UK jobs and communities linked to the defence industry through diversification plans”
Biggest unknown: Whether a Defence Diversification Agency or equivalent could realistically retrain and redeploy specialist nuclear workers into comparable-quality jobs at scale and speed.
Our reading: The clearest O4 effect of this policy is the direct loss of a large number of above-average-wage jobs. The DNE currently employs around 47,600 people at wages 20% above the national average, concentrated in specific communities. Cancelling Trident and the Dreadnought replacement would eliminate or sharply curtail this employment base, with Barrow-in-Furness being the most exposed location. These are not generic jobs easily absorbed by a local labour market — they are specialist, high-skill, high-pay roles in a niche sector. The short-to-medium-term distributional harm to affected workers is therefore real and significant. The countervailing argument — that savings could be redirected to create more and better jobs elsewhere — comes primarily from CND (an advocacy source) and is not grounded in any committed instrument, budget allocation, or statutory mechanism within the policy itself. The TUC has separately called for diversification plans, but again without a funded delivery vehicle cited in the evidence. The soft-verb rule applies: the policy promises cancellation but contains no binding diversification guarantee. On the evidence provided, the direction on O4 is a worsening: a moderate number of well-paid, secure jobs in specific communities would be lost, with no evidenced-at-scale replacement mechanism. CND's figures (11,520 directly dependent) and government figures (47,600 across the DNE) differ substantially; even the lower estimate represents a meaningful concentration of employment harm. Confidence is moderate because the diversification question is genuinely uncertain, but the near-term job-loss effect is well-evidenced.
Crime, justice & national security — Hurts
moderate · moderate confidence
Cancelling Trident and signing the TPNW would remove the UK's nuclear deterrent, weakening its national security posture and its role within NATO's collective defence. Whether nuclear weapons actually deter threats is genuinely disputed, but the mainstream defence consensus and the UK's current strategic doctrine treat the deterrent as a core security instrument.
The evidence
- The policy would cancel Trident, dismantle nuclear weapons, push to sign the TPNW, and remove all foreign nuclear weapons from UK soil. — greenparty.org.uk (manifesto) — “Push for the UK to sign the UN Treaty on the Prohibition of Nuclear Weapons (TPNW), dismantle nuclear weapons, cancel the Trident programme, and remove all foreign nuclear weapons from UK soil.”
- The UK currently operates a continuous at-sea deterrent assigned to NATO's collective defence. — commonslibrary.parliament.uk (government) — “The UK currently operates a "minimal credible nuclear deterrence" assigned to the defence of NATO, maintaining a continuous at-sea deterrent”
- Signing the TPNW would legally oblige the UK to prohibit deployment of nuclear weapons on its territory. — commonslibrary.parliament.uk (government) — “Signing the TPNW would legally oblige the UK to "prohibit and prevent the stationing, installation, or deployment of nuclear weapons on their territory"”
- None of the nine nuclear weapon states have signed the TPNW; the UK has consistently voted against UN resolutions welcoming it. — commonslibrary.parliament.uk (government) — “None of the nine nuclear weapon states, including the UK, have signed or ratified the TPNW, and the UK has consistently voted against UN resolutions welcoming it”
- Proponents of deterrence argue nuclear weapons are essential for deterring nuclear blackmail and maintaining UK security within NATO. — nuclearinfo.org (media) — “Proponents argue that nuclear weapons are essential for deterring unspecified threats, nuclear blackmail, and maintaining the UK's security within NATO”
- Opponents argue nuclear weapons have little utility against modern threats such as terrorism or cyber warfare and may increase proliferation risk. — cnduk.org (media) — “Opponents question the military utility of nuclear weapons against modern threats like terrorism or cyber warfare and argue that their existence might even increase the risk of nuclear proliferation”
- Many military personnel support retaining nuclear weapons, viewing deterrence as their primary function. — nuclearinfo.org (media) — “Many military personnel, as noted in one report, support the UK retaining nuclear weapons, viewing deterrence as their primary function”
Biggest unknown: Whether nuclear deterrence materially reduces the probability of state-on-state aggression against the UK — if deterrence theory is wrong or obsolete, the security cost of abolition is lower than assessed here.
Our reading: The O5 fundamental includes national security and defence posture as core indicators. The policy would eliminate the UK's nuclear deterrent entirely and legally prevent hosting allied nuclear weapons. The UK's current doctrine treats the continuous at-sea deterrent as the cornerstone of its national security against state-level threats, assigned to NATO's collective defence. Unilateral disarmament would remove this capability permanently. No evidence unit suggests the UK could replace the deterrent effect with alternative non-nuclear means at comparable scale. The primary counter-argument — that nuclear weapons are irrelevant to modern threats like terrorism or cyber — is real and cited, but it addresses a subset of the threat landscape rather than state-on-state or nuclear coercion scenarios, which are the threats deterrence is specifically designed to address. The fact that no other nuclear-armed state has signed the TPNW, and that the UK has actively opposed it in UN fora, reflects the mainstream institutional view that abandoning deterrence unilaterally degrades security. Decommissioning costs and transition disruption are noted in the evidence but are secondary to the strategic security effect for this outcome. The verdict is 'worsens/moderate' rather than 'major' because deterrence theory is contested and the actual probability-reduction effect of nuclear weapons is not precisely quantifiable; confidence is moderate for the same reason.