The UK’s defence dilemma 

George Buchan explores the growing debate over UK defence spending amid an increasingly uncertain global security environment.


Image by mehaniq | Magnific

Events surrounding the strait of Hormuz, owing to the US-Iran conflict in February, have highlighted the shortcomings in UK defence spending. The conflict involved attacks on shipping and disruptions to one of the world’s most important energy routes, and while the UK did not participate in the strikes, British aircraft and other military assets were subsequently used in operations across the region – and the UK allowed the US to launch such operations utilising British bases as of July 23. Such a crisis has renewed a rather familiar question spread across political discourse: how much should the UK spend on defence?

Roughly a fifth of Britain’s current defence budget goes to nuclear submarines, which has left conventional forces stretched thin, but the force’s structure is partly a consequence of choices made when the strategic environment looked very different. The reduced size of the Royal Navy acts as one example of decades of the shift away from defence, with spending dropping from 3.8 per cent of GDP in the early 1990s to 2.3 per cent in 2024. 

The shift, notably, came following the collapse of the Soviet Union, with the 1990s peace dividend allowing resources to be directed towards other priorities. This, however, was challenged with incidents, such as Russia’s full-scale invasion of Ukraine in 2022 and attacks on commercial shipping in the Red Sea, demonstrating how quickly developments far from the UK can have consequences for British security and economic interests.

It appears, though, that Britain has already begun to answer the first question. Defence spending is scheduled to rise to 2.6 per cent of GDP by 2027, with an ambition to reach three per cent in the next Parliament, subject to economic and fiscal conditions, while the Secretary of State for Defence, John Healey, described the current environment to be: “more serious and less predictable than at any time since the Cold War.” The Government’s 2026 Defence Investment Plan subsequently sets out a total of £298 billion of investment over the next four years, making it 27 per cent higher than 2023. 

The problem of an increase in spending, however, relies heavily on how far the public is prepared to accept the cost – and so far, it seems that spending may not change owing to three key perception issues: a lack of salience, a lack of knowledge, and other conflicting priorities. 

Security at home

Firstly, defence feels distant and secondary to most Britons, tucked away in headlines about far-off seas rather than day-to-day existence. As an island nation insulated from immediate continental threats post-Cold War, for many, it seemed sensible to slash budgets as threats receded, while health, the economy, immigration, housing, and the cost of living tended to be more immediate concerns. 

Recent events, however, have made the connection between geopolitical instability and everyday economic security harder to ignore, nonetheless, and it is evident through polling results. An Ipsos polling conducted in June 2026 found that while 47 per cent of Britons believed government spending on defence and the Armed Forces should increase, 45 per cent would oppose an increase if it meant less money for public services, while 50 per cent would oppose it if it meant higher personal taxes. 

Even with the increase in salience, however, there remains a considerable information challenge. Public understanding of the UK's current military capabilities is often uneven, which may make it difficult for voters to assess competing arguments about defence spending.

Many surveys, in particular, reveal various misconceptions the public contains. For instance, some believe the UK has a large standing army, unaware it has been reduced to under 75,000 regulars. The navy surface ships number fewer than 20, with delays and issues hindering the effect of new carriers, while the air force fast jets hover around 130. This persists owing to defence’s opaque nature. Jargon such as ‘swing-role platforms’ or ‘strategic enablers’ alienates many. People know Trident costs billions but not that it consumes a fifth of the budget, meaning less for conventional forces.

Conflicting priorities form the last and toughest barrier. For many voters, issues that affect them and their loved ones, including hospital waiting lists, crumbling schools, and cost-of-living squeezes over defence. This pressure is even harder post-Covid-19, when public debt is at 100 per cent of GDP, which makes tax hikes a prospect for any politician.

While the UK continues to face such public discourses, one possible response is through awareness, especially campaigns where security, everyday life, and economic resilience interact, best illustrated through the disruptions to the Strait of Hormuz. When 25 per cent of global oil passes through a certain route, disruptions to this economic passage spike fuel prices at the pump, directly hitting household budgets. A blockade could add 20 per cent to oil costs overnight and cost the UK economy £50 billion yearly in disrupted imports, per energy analysts, translating to £200 extra annually per household. 

Awareness could also aid in reducing misconceptions around defence. A campaign does not have to involve making the whole of the UK experts on defence. Rather, clear communication through education campaigns can help citizens make informed decisions on defence spending. Simple comparisons can help make complex issues more tangible, whether it be explaining the size and composition of the British Army relative to other European forces or setting out the scale of Germany’s recent investment in defence.

The changing security environment across the globe raises legitimate discourse about how much the UK should spend on defence, but there is, ultimately, no simple answer. As competing public priorities and uncertainty over how additional spending should be allocated continue, the challenge for policymakers then becomes how they can strengthen the UK’s security without placing pressure on services and households under pressure.

George Buchan is the founder of George Buchan Insight, an organisation that conducts research programmes for market-leading companies and political parties across the UK and internationally.