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Chair, MTCR
May 19, 2021
UK Review Doubts Trident Alternatives

Robert Golan-Vilella

Nearly all of the leading alternatives to the United Kingdom’s current plan for replacing its nuclear-armed submarines would cost more than the existing approach, a British government study found recently.

The “Trident Alternatives Review,” which was published July 16, examined alternative plans for the replacement of the United Kingdom’s four aging nuclear-armed submarines. The current plan of “like-for-like” renewal, championed by Prime Minister David Cameron, would involve replacing each of the retiring submarines, which are scheduled to reach the end of their service lives in the late 2020s and early 2030s, with a new successor model, which is yet to be developed.

The 64-page report, drafted by officials in the Cabinet Office, considered a variety of plans for fielding an arsenal composed of nuclear-tipped cruise missiles instead of ballistic missiles. The cruise missiles could be deployed on surface ships, submarines, or aircraft.

The report determined that all such options would be more expensive than like-for-like replacement, mainly due to the time required to produce the new weapons systems. The review concluded that a new cruise missile warhead could not be developed and deployed until about 2040, well after the current submarines had left service. The cruise missile options therefore would require the United Kingdom to build two additional nuclear-armed submarines to “bridge the gap” until a cruise missile-based system was ready for use, adding to their costs.

The study estimated that like-for-like replacement would cost approximately 20 billion pounds ($31 billion) over the life cycle of the new submarines. The only cheaper option would be to replace the county’s four Vanguard-class submarines with a fleet of three vessels, according to the report. However, it noted that doing so would force London to abandon its current posture of “continuous at-sea deterrence,” in which at least one of the submarines is kept on patrol at all times.

The review considered a range of other potential nuclear postures but concluded that none of them offered “the same degree of resilience as the current posture.” Whether any of these alternatives would constitute a viable option for the country would depend on a political calculation by the government concerning the amount of risk it would be willing to take, the review said.

Currently, the United Kingdom’s entire operational nuclear arsenal is deployed on the four submarines, each of which is armed with Trident ballistic missiles. As of 2010, London’s stockpile consisted of no more than 225 nuclear weapons, of which fewer than 160 were actively deployed, according to government figures. Those numbers are scheduled to be reduced to 180 and 120, respectively, by the mid-2020s. (See ACT, November 2010.)

The impetus for the review came from the Liberal Democrats, who in 2010 assumed power in a coalition government along with Cameron’s Conservative Party. The two parties pledged to maintain the country’s nuclear deterrent, but also agreed that plans for the replacement of its nuclear weapons systems would be “scrutinised to ensure value for money” and that the Liberal Democrats would “continue to make the case for alternatives.” The following year, the coalition government formally commissioned the Trident review.

With the review’s completion, the Conservative Party leadership argued that the report bolstered the case for like-for-like replacement.

“The Government remains 100 per cent committed to maintaining and renewing the Trident system,” Defence Secretary Philip Hammond wrote in the July 15 Daily Mail. Hammond added that “the logic for this commitment is clear: there is no alternative to Trident that provides the same level of protection and ability to deter an aggressor. The alternatives are less capable, less credible and more expensive.”

In contrast, Danny Alexander, the chief secretary to the treasury and lead minister of the review, sought to paint the review as a potential catalyst for change. Speaking in London at the report’s launch, Alexander, a Liberal Democrat, argued that the review demonstrated “that there are credible and viable alternatives to the United Kingdom’s current approach to nuclear deterrence.” The posture of continuous at-sea deterrence has become “unnecessary,” Alexander asserted. By ending this posture and moving from four submarines to three, he said, the government could save 4 billion pounds over the life of the systems.

Paul Ingram, executive director of the British American Security Information Council, told Global Security Newswire on July 16 that “the limits of the review are clear. It interprets credibility strictly, and does not consider any options that do not have the capacity of reinstituting continuous at-sea deterrence at a moment’s notice.”

The United Kingdom approved the preliminary “initial gate” investment in the new submarines in 2011, allowing preparatory work on the replacement to proceed. (See ACT, June 2011.) The “main gate” decision to begin construction on the submarines is scheduled to be made in 2016. This would be after the next British general elections, which are slated to take place no later than May 2015.