Under-Invested and Directionless

As Chief of the Defence Staff, Admiral Sir Tony Radakin warned a few years ago: “You cannot turn defence on and off like a tap. Once capability is lost, it takes years to rebuild.” That warning feels more relevant than ever.

Much has already been written about why the UK’s delayed Defence Investment Plan matters strategically. The absence of a clear roadmap raises questions about credibility, alliance coordination and the ability to convert defence ambition into funded capability.

But the real impact is not only strategic, it is industrial.

Across the defence sector, the technological direction is becoming increasingly clear. Autonomy is advancing, AI is progressing rapidly and new capabilities are moving from concept toward deployment. Industry understands where capability is heading.

What it does not understand is when investment will follow.

The Defence Investment Plan was intended to translate defence strategy into funded programmes and timelines. Its continued delay means much of the sector is still waiting for clarity about priorities and sequencing. Without that clarity, the industry cannot move forward with confidence.

Ambition alone does not sustain an industrial base. Capability is built on confirmed funding, programme timelines and long-term commitments.

The Industry Is Frozen

Across the defence sector, companies are delaying recruitment, holding back capital investment and slowing research activity while they wait for clearer signals from government. This uncertainty is particularly challenging for smaller suppliers deeper in the supply chain, where margins are tighter and the risk of investing ahead of confirmed programmes is harder to absorb.

Defence manufacturing depends on continuity. Skilled engineers cannot simply be switched on and off in line with shifting timelines. Once those skills leave the sector, they are difficult to replace.

Parliamentary committees have already warned about the risks the current uncertainty creates. In a joint letter, the Defence and Public Accounts Committee chairs cautioned that further delays to the plan could “risk sending damaging signals to adversaries.”

Those signals are also being felt across the industrial base itself.

Sovereign Capability Has a Cost

Maintaining sovereign defence capability requires sustained investment. Skills, facilities and supply chains cannot be maintained indefinitely without long-term programmes to support them.

Sovereign capability cannot simply be declared as a policy objective, it has to be paid for.

For industry, that means long-term commitments. Contracts that run six, ten or even twelve years allow companies to invest in people, infrastructure and technology with confidence. Without that continuity, maintaining capability becomes increasingly difficult.

Expecting industry to sustain critical defence capabilities without clear long-term investment creates a structural problem. Companies cannot carry the cost indefinitely while waiting for government direction.

If the UK is serious about maintaining sovereign capability, then sustained investment and long-term contracts must be part of the solution.

Strategic Patience vs Political Cycles

Part of the challenge lies in how defence capability is planned.

Many of the UK’s strategic competitors operate on long time horizons, often planning capability development over 15-30- or even 50-year cycles. This allows them to invest consistently in industrial capacity, technology development and force structure.

By contrast, the UK system often operates within much shorter political cycles. Funding decisions are frequently tied to spending reviews and electoral timelines, creating uncertainty that makes long-term planning difficult.

The result is that key areas of defence capability have historically been under-invested. Armed forces have been reduced in size and the industrial base has often been expected to maintain sovereign capability without the sustained investment required to support it.

Defence capability is not built on short-term cycles. It requires patience, consistency and long-term planning.

Waiting Carries Its Own Risk

The bottom line is that the UK defence sector has the technology, expertise and industrial base to deliver the next generation of capability. What is holding it back is not ambition or capability, but the continued delay in providing the clarity industry needs to invest and move forward.

The Defence Investment Plan was supposed to provide that clarity. Instead, the prolonged wait is leaving the sector in a holding pattern. Until direction is defined, the industry will remain caught between ambition and execution — ready to move forward, but waiting for the signal to do so.

And in a strategic environment where competitors are planning decades ahead, waiting carries its own risk.