A brief guide to previous British defence reviews

The Government is refreshing its 2021 Integrated Review of security, defence, development and foreign policy. This is to reflect the changing security environment following Russia’s invasion of Ukraine in February 2022. The update is expected to be published around the time of the Spring Budget 2023, which is scheduled for 15 March 2023.

About defence reviews

A defence review enables a government to present a forward-looking assessment of Britain’s strategic interests and requisite military requirements. It examines the defence and security landscape, identifies current and emerging threats and then decides how best to organise and equip the Armed Forces.

Evolution of British defence reviews

The current practice of undertaking a strategic defence and security review every five years dates back to 2010.

The first major, wholesale strategic defence review post World War Two is widely considered to be the Sandys Review in 1957. There has been at least one defence review in every decade since then at irregular intervals. This paper briefly discusses each of these.

The 2010 Government committed to holding an SDSR every five years, arguing “one clear lesson since the last Strategic Defence Review in 1998 is the need more frequently to reassess capabilities against a changing strategic environment.”

The new Conservative Government duly held a fresh NSS/SDSR in 2015.

The early election in 2017, combined with concerns about the changing security environment, prompted calls for a fresh SDSR. Instead, the Government opted for a National Security Capabilities Review and a Modernising Defence Programme.

Recent reiterations have broadened beyond purely defence considerations. The 2010 SDR was published alongside a National Security Review (NSS). By 2015 they were interwoven in one document. Catarina Thomson and David Blagden explain how they interact:

While the NSS assesses leves of security risk to the United Kingdom and appropriate strategic responses, the SDSR seeks to procure and assign forces/capabilities to address such risks. The SDSR process is thus intended to conduct comprehensive, corss-departmental analysis of national security/defence needs, in line with the NSS, before setting/allocating resources via capability choices. 

The 2021 Integrated Review

In December 2019 the Johnson Government announced plans to conduct an Integrated Review of security, defence, development and foreign policy. This was subsequently published in March 2021.

Entitled Global Britain in a Competitive Age, the review sets out the government’s overarching national security and international policy objectives to 2025. The review decribes Chinas as the “biggest state-based threat to the UK’s economic security“, while Russia “remains the most acute threat to our security” in the Euro-Atlantic region. The review also indicates a tilt towards the Indo-Pacific, in recognition of the region’s growing importance. The Government also decided to raise the cap on the UK’s nuclear stockpile, for the first time since the end of the Cold War.

The review was accompanied by a Defence Command Paper, Defence in a Competitive Age, and a Defence and Security Industrial Strategy.

The Library produced a series of papers examining the Integrated Review and Command Paper, collated on one webpage: The Integrated Review 2021.

The 2023 refresh of the Integrated Review

The government has undertaken a refresh of the Integrated Review. It is expected to be published around the time of the Spring Budget 2023, which is scheduled for 15 March 2023.