As former Nato chief warns about defence spending, how much has the military shrunk?

UK Military Shrinkage and Defense Spending Concerns

As the UK’s security faces evolving threats, a former NATO leader has raised alarms about the nation’s decreasing military strength. Lord Robertson, who chaired the Strategic Defence Review (SDR) last year, claims the current defense strategy leaves Britain vulnerable. His warning underscores a growing worry: the country may be unable to protect itself with a welfare system that continues to expand.

“We cannot defend Britain with an ever-expanding welfare budget.”

Historical Comparisons Show a Decline

Since the end of the Cold War in 1990, the UK military has seen significant reductions. The army, which once boasted 153,000 regular troops, now stands at 73,790. The 2025 SDR aimed to stabilize the force at 73,000, yet recruitment applications have dropped by roughly 40% in the same year. Meanwhile, the number of reservists has plummeted from 76,000 to 25,770, highlighting a broader trend of shrinking military readiness.

The Royal Navy’s fleet has also shrunk. In 1990, it had 48 major combat ships, including 13 destroyers and 35 frigates. Today, it operates just 11 frigates and six destroyers. The RAF, once equipped with over 300 combat jets, now relies on a mix of 137 Eurofighter Typhoons and at least 37 F-35 Lightning II aircraft, which are more advanced but fewer in number. The rise of uncrewed aerial systems, or drones, has further transformed the landscape, with these technologies playing a key role in modern warfare, as seen in Ukraine’s conflict.

Government Response and Spending Targets

The UK government has defended its approach, stating it plans to boost defense spending to the highest level since the Cold War. However, critics argue this is a modest goal given the long-term decline in defense budgets following the fall of the Berlin Wall. Officials aim to allocate 2.5% of GDP to NATO-qualified defense spending by April 2027, with an ambition to reach 3% in the next parliamentary session.

Lord Robertson emphasized the imbalance between defense and welfare spending, noting that the latter has grown beyond its 1980s levels. By the end of the decade, welfare expenditures are projected to hit 4.3% of GDP, driven in part by increased claims for Personal Independence Payments (PIP). While mental health conditions may explain some of this growth, experts remain unsure of the full drivers behind the trend.

Procurement Challenges and Project Delays

Despite its commitments, the Ministry of Defence (MoD) faces hurdles in modernizing its forces. The NAO’s December report revealed that 12 of the 47 major procurement projects in the MoD’s portfolio were rated “Red,” meaning their success is uncertain. Over years, the MoD has struggled to meet deadlines, costs, and performance standards for many initiatives.

For projects exceeding £20 million, the average time to finalize contracts now stretches to six and a half years. The 2025 SDR proposed a “segmented approach” to speed up this process, aiming to deliver contracts within two years. Analysts stress that the UK must invest more in cutting-edge technologies like drones to counter emerging threats, even as its conventional military capabilities shrink.

Global Context and Future Goals

As of 2025, the UK spends 2.3% of GDP on defense, placing it near the midpoint of NATO members’ contributions. The alliance has set a target for the UK to reach 5% of GDP on national security by 2035, divided into 3.5% for core defense and 1.5% for infrastructure protection and civil preparedness. Only three nations—Poland, Lithuania, and Latvia—exceeded the 3.5% threshold in 2025, with Estonia and Norway nearly matching it.

Analysts cite rising tensions with Russia since 2022, ongoing conflicts in the Middle East, and uncertainty about the US’s NATO commitment as critical factors justifying the need for increased defense investment. The question remains: can the UK’s shrinking military adapt quickly enough to meet these challenges?