Conservatives defend £10bn Britannia Shield after Iron Dome comparison

The Conservatives have announced a £10 billion air and missile defence programme called Britannia Shield, promising to build it if they return to power. The pledge was made at the party conference in Birmingham. Shadow Defence Secretary James Cartlidge said it would be the most significant upgrade to UK air defence for generations. The party says the system would cost about £1 billion a year over 10 years and would protect the UK and its overseas bases from drone and missile attack.

Under the plan, Britannia Shield would have three main parts. They are advanced mobile radars, major upgrades to command and control systems, and deep stockpiles of interceptor missiles. Cartlidge described the system as sense, decide, effect: seeing the threat, deciding quickly how to deal with it, and intercepting it. He said a Conservative government would start building on day one in office rather than wait for a strategic defence review. The Tories say the system would protect critical national infrastructure and military bases, and that it would also act as a deterrent.

The announcement was initially presented as being similar to Israel's Iron Dome. A press release described the plan as, in essence, a British Iron Dome. But Kemi Badenoch later played down the comparison. She said the UK was not replicating the Israeli system, which is designed for short-range rockets. She said Britannia Shield would focus on longer-range drone and missile threats, including from Russia and Iran. She also said it would protect critical national infrastructure rather than offer the same kind of blanket reassurance to the whole population that the Iron Dome gives Israel. Asked whether the system would cover the whole country, she said protecting key infrastructure meant the whole country was protected because an attack on it would threaten everyone.

Military experts have questioned both the cost and the reach of the plan. General Sir Richard Barrons, former commander of Joint Forces Command, said a true Iron Dome-like capability over the UK's major metropolitan areas could cost between $75 billion and more than $100 billion over 10 years. Other experts said £10 billion was about one tenth of what would be needed to replicate the Iron Dome. They warned that interceptor missiles are far more expensive than the cheap drones they would be used against, so the cost rises with every attack. Questions also remain about how much of the UK could be protected and whether the system would cover only military sites and critical infrastructure.

Funding is central to the political row. The Conservatives say the £10 billion is affordable because they have a fully costed plan to reach 3 per cent of GDP on defence by 2030. They say it would be paid for in part by cuts to welfare and net zero funding, and by reallocating money from research budgets. Labour says the Tories hollowed out the armed forces and underfunded defence during their time in government. The government says the Conservatives cannot be trusted with national security. Labour has promised to reach 3 per cent of GDP on defence in the next parliament, but has not set a date. Reports suggest the decision could be delayed until next autumn. The government's current air and missile defence plan is around £70 million a year, while the Tories are proposing about £1 billion a year. The Tories say Labour has committed only £790 million in additional funding to integrated missile and air defence.

The announcement came amid renewed concern about threats to UK bases. US B-1 bombers were withdrawn from RAF Fairford after what was described as an Iranian drone threat. Police have arrested seven men in connection with a suspected terror plot near the base. A 22-year-old British national was arrested in London on suspicion of preparation of terrorist acts. Intelligence reports suggested a more complex attack was being planned, including drones and follow-up attacks from multiple vectors. An IRGC agent was believed to be directing some of those involved, and a manhunt was under way. Kemi Badenoch cited Iran and Russia as hostile states that have threatened the UK, and said she did not want to wait until something bad happened before acting.

The UK plan echoes wider international moves on missile defence. In the United States, President Donald Trump has promoted a Golden Dome system, originally called an Iron Dome for America. Its cost has been estimated at up to $1.2 trillion over 20 years, and most of the requested funding depends on legislation that could be blocked if Republicans lose control of Congress. Experts say such programmes face long-term political and fiscal challenges, not just technical ones. For the UK, the debate is smaller in scale but similar in shape: how much protection can be bought, how quickly, and at what long-term cost.

At the conference, defence was used as a dividing line. Tory activists gave James Cartlidge a strong reception, and the party hopes the pledge will put pressure on Labour over its own defence spending plans. But the plan will face scrutiny on whether the numbers add up, whether the system can be delivered, and whether it would protect the country in the way the branding suggests. As one former commander put it, an air defence system should be a high priority, but a full Iron Dome-style shield for the UK would cost far more than the £10 billion on offer.