Lib Dems forced to embrace Trident deterrent

Liberal Democrat Treasury Minister Danny Alexander, who was in charge of the review, wants to reduce the Trident submarine fleet from four boats to three, but is on collision course with his Conservative coalition partners who back like-for-like replacement to maintain round-the-clock patrols.

The Liberal Democrat party opposes full-on replacement of the Trident system at a cost of £25bn, although the review published today has effectively rejected any alternatives as less effective and too expensive.

This morning the Conservative defence secretary, Philip Hammond, said it would be “naïve or reckless” to opt for a “part-time” deterrent by reducing the number of submarines to fewer than four.

He echoed the sentiments of five former defence secretaries from both the Conservative and Labour parties, who today wrote to the Daily Telegraph to condemn a watering down of the current deterrent system.

The part-time deterrent will save us only trival sums of money. Philip Hammond, defence secretary

“We can have continuous at-sea nuclear deterrence or we can have a part-time deterrent,” said Hammond. “The part-time deterrent will save us only trivial sums of money – about £50-60m a year. And in the context of the overall defence budget, that’s about 0.17 per cent. That’s a tiny saving for a huge gamble with Britain’s security.”

Mr Alexander said today he hoped the review would be “the start of a major debate rather than the end of one”.

“Nuclear deterrence is one of the few areas of our defence policy that hasn’t moved on very much since the end of the cold war. What we want to do is move away from 24-hour patrol when we don’t need it, still having the capacity to surge back to that level if it’s needed when we see a threat escalating in the future.”

He claimed that £4bn could be saved by opting for three submarines instead of four. “We can buy fewer submarines – that makes a cost saving long into the future and keeps out country safe.”

Long-term threat

This morning the prime minister, David Cameron, reiterated his support for a like-for-like replacement while Mr Hammond dismissed the Liberal Democrats’ preference for a lesser deterrent.

“Just because we don’t perceive an immediate threat today doesn’t mean that there won’t be a threat over the 60 year-odd time horizon we’re looking at here,” Mr Hammond said.

“We’re talking about a deterrent that would be deploying in the 2030s that would still be in service in the 2060s. We’ve got countries like Iran and North Korea trying to build nuclear weapons and already possessing long-range missiles.

“We can’t say who the potential adversary might be in the future: Russia is investing over $150bn in renewing its forces.”

Read more from Political Editor Gary Gibbon: Going nuclear over Britain's defences

The review was a political fudge borne of the coalition agreement in 2010, which committed to a cost-saving review of Trident in a concession to the Liberal Democrats’ opposition to the deterrent.

The review considered whether Britain should adopt an air-based deterrent or arm submarine-based cruise missiles with nuclear tips, but found that these alternatives would be less effective and more expensive than the current Trident system.

Britain’s current Vanguard submarines will need to be replaced in the next 15-20 years if the Trident system is to be retained. A final decision on replacement needs to be taken in 2016, although significant design work has already begun due to the time it takes to build the highly advanced successor submarines.

Why four submarines?

Using four submarines is seen as crucial by the Ministry of Defence in maintaining the 24-hour deterrent that has operated for the last 45 years, by providing cover for unforeseen events.

The Royal Navy has one submarine on operations at any time, with the second on training exercises. This leaves the third submarine in “deep maintenance” while the fourth undergoes minor refit at short notice of going operational if needed.

A Cabinet Office spokesman said the review did not examine a long-term fleet of two successor submarines, “as such a force would be unable to guarantee the availability of an assured, credible deterrent capability for a sustained period”.

A two-submarine solution “would only be able to sustain an at-sea deterrence posture for a few months at a time and hence was not considered credible by the review,” he added.

Lord West, the former first sea lord, has warned that opting out of covert 24-hour operation by the Trident-based deterrent risks escalating any potential conflict scenario, if adversaries become aware that Britain is deploying a Trident-equipped submarine.