A senior Labour grandee has delivered one of the most pointed critiques yet of Sir Keir Starmer’s approach to defence, raising not only questions about funding, but about the coherence—and, in some quarters, the competence—of the government’s wider security posture.

The intervention by George Robertson, himself a former defence secretary and architect of Labour’s 2025 Strategic Defence Review, was striking for its tone as much as its substance. Britain’s national security, he warned, is “in peril”, the result of what he termed “corrosive complacency” at the top of government.

At one level, the dispute centres on money. Starmer has pledged to raise defence spending to 3 per cent of GDP during the next parliament, a commitment designed to reassure NATO allies and signal seriousness in an era of renewed geopolitical tension. Yet Robertson and others argue that such promises ring hollow without a credible plan to deliver them. The long-awaited 10-year investment blueprint remains unpublished, while gaps in capability—from ammunition to cyber resilience—continue to widen.

But the criticism now extends well beyond budget lines. Robertson’s central charge is that there is a fundamental disconnect between rhetoric and reality: that the Prime Minister speaks the language of strategic urgency, while presiding over what critics see as drift. He is said to have remarked privately that Starmer is “not willing to make the necessary investment”, pointing to a failure of political will rather than mere fiscal constraint.

This sentiment has found echoes elsewhere. Former senior military figures, including General Sir Richard Barrons, have warned of a substantial funding shortfall—estimated at around £28 billion—and questioned whether Britain’s armed forces are currently capable of meeting modern threats. The implication is not simply that resources are insufficient, but that strategic priorities are unclear.

Indeed, some critics go further, suggesting that Starmer’s leadership style itself may be ill-suited to the demands of defence policy. His instinct for caution—often an asset in domestic politics—has, in the security sphere, been interpreted by detractors as hesitation. The government’s handling of the 2026 Iran crisis is frequently cited in this regard. Starmer initially declined to support US-led strikes, later permitting limited use of British bases only after delay, a sequence that drew criticism both at home and abroad.

That episode prompted unusually blunt remarks from Washington. Donald Trump was reported to have complained that the British Prime Minister had “not been helpful”, even remarking that “this is not Winston Churchill that we’re dealing with”. While such language may be dismissed as characteristic of the former president’s style, it nevertheless points to strains within the so-called “special relationship” at a time when unity might be expected.

Domestic opponents have been no less forthright. Conservative leader Kemi Badenoch has accused the government of prioritising welfare over defence, arguing that Britain risks strategic decline if spending priorities are not rebalanced. Even allowing for partisan exaggeration, the line of attack has gained traction amid wider concern about the state of the armed forces.

There are, too, questions about strategic consistency. Starmer has sought closer alignment with the European Union on security and economic matters, presenting this as a pragmatic response to global instability. Yet critics argue that such moves risk diluting Britain’s autonomy without delivering immediate gains in military capability. Others point to his government’s approach to China—described as “pragmatic” engagement despite acknowledged security risks—as evidence of an uneasy balancing act between economic and strategic priorities.

None of this is to suggest that the government lacks a framework. The Strategic Defence Review, commissioned shortly after Labour took office, represents a serious attempt to rethink Britain’s military posture for a new era, emphasising drones, data, and digital warfare. Ministers insist that more than £270 billion will be committed to defence over the coming years, and that Britain remains aligned with NATO’s evolving strategy.

Yet the charge, increasingly heard, is that strategy without execution amounts to little. Robertson’s criticism of the Treasury—accused of giving scant attention to defence in key fiscal statements—hints at deeper dysfunction within government, where competing priorities have yet to be reconciled.

The broader context only sharpens the debate. From Ukraine to the Middle East, the international environment has become more volatile, while uncertainty over the future direction of US foreign policy has placed greater pressure on European allies to shoulder more of the burden. In such circumstances, questions about Britain’s preparedness take on added urgency.

For Keir Starmer, the political risk is clear. Defence has historically been an area where perceptions of leadership matter as much as policy detail. A prime minister seen as hesitant, or insufficiently committed to national security, can quickly find himself on the defensive—particularly when criticism comes from figures within his own political tradition.

To his supporters, however, the Prime Minister’s caution reflects a deliberate effort to avoid the strategic overreach that characterised earlier interventions, notably in Iraq. His insistence on legal clarity and defined objectives in the Iran crisis can be read as prudence rather than indecision.

The difficulty lies in reconciling that instinct with the demands of deterrence. In an era of heightened tension, ambiguity can be read not as restraint, but as weakness. Robertson’s warning, for all its severity, is ultimately a call for clarity: of purpose, of funding, and of leadership.

Whether Starmer can provide it remains an open question—one that will shape not only his premiership, but Britain’s place in an increasingly uncertain world.

“No Winston Churchill”: Keir Starmer’s Credibility Shrinks with the Royal Navy