Ed Miliband: Climate breakdown is one of the greatest national security threats and is causing food insecurity, infrastructure threats, and population movements. Our verdict: True.
Ed Miliband made the statement to The Guardian on 11 November 2026, ahead of his planned speech at COP31.
Our verdict
True
Ed Miliband did say that climate breakdown is one of the greatest national security threats and that it is causing food insecurity, infrastructure threats and population movements. Official UK and US documents back up each of those points, so the claim is accurate.
What we found
We checked what Ed Miliband actually said and whether the impacts he listed are recognised by official sources. The Guardian reported his statement directly, and other outlets recorded him making the same point in public. The 2025 UK National Security Strategy links the climate crisis to national security, food insecurity, pressure on infrastructure, and migration. The US Department of State also treats climate change as a national security challenge with those same effects, and UNHCR identifies climate change as a driver of displacement. A UK Joint Intelligence Committee report, as reported by The Guardian, names food shortages and migration as key climate-related security risks. Nothing we found contradicts the claim.
The evidence
5 of 6 sources support the claim; none contradict it.
- Background
The Guardian reported that Ed Miliband said climate breakdown is one of the greatest national security threats we face, and that it drives food insecurity, infrastructure threats and population movements. [1]
- Supports the claim
The 2025 UK National Security Strategy explicitly links the climate crisis to national security, food insecurity, infrastructure pressure and migration. [2]
- Supports the claim
The US Department of State officially categorises climate change as a national security challenge involving food insecurity, infrastructure damage and migration. [3]
- Supports the claim
UNHCR identifies climate change as a driver of displacement and a factor in international peace and security. [4]
- Supports the claim
A UK Joint Intelligence Committee report, as reported by The Guardian, identifies the climate crisis as a major national security risk, citing food shortages and migration as key impacts. [5]
- Supports the claim
The UK government's climate security taskforce announcement identifies climate-related security risks with potential effects on migration and food access, and says infrastructure and assets are exposed to risk. [6]
What we could not confirm
- We could not independently verify the scientific magnitude of the ranking that climate breakdown is one of the greatest national security threats, beyond the stated positions of the UK and US governments.
- The evidence is concentrated in UK and US policy documents, so the claim's global framing is not fully tested across other countries.
How we checked
We looked at the original Guardian report of the statement, UK government strategy and taskforce documents, US State Department material, UNHCR guidance, and Guardian reporting on UK intelligence findings. We checked whether each part of the claim — national security, food insecurity, infrastructure threats and population movements — was backed by an official or on-the-record source. We reviewed 11 relevant sources.
Sources
- [1]The Guardian · Ed Miliband: climate crisis puts national security of all countries at risk · November 11, 2026
- [2]assets.publishing.service.gov.uk · National Security Strategy 2025 · June 1, 2025
- [3]2021-2025.state.gov · Climate Change as a National Security Challenge - United States Department of State · October 21, 2024
- [4]unhcr.org · CLIMATE CHANGE AND DISASTER DISPLACEMENT · January 1, 2017
- [5]theguardian.com · National security threatened by climate crisis, UK intelligence chiefs due to warn · October 8, 2025
- [6]UK Government · UK launches first ever taskforce to strengthen climate security · June 26, 2026
Have evidence we missed?
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