The Red Arrows perform a flypast during an armed forces and veterans' parade on the final day of VE day commemorations in central London, May 10, 2015.
Suzanne Plunkett / Reuters

In what was one of the biggest upsets of the May 7 British general election, Mhairi Black, a 20-year-old University of Glasgow student and candidate for the Scottish National Party (SNP), unseated Douglas Alexander, the Labour Party’s campaign architect and former Shadow Foreign Secretary, in a district he had represented for nearly 20 years. In her victory speech, televised across the country, she declared to thunderous applause, “I will always vote against wasting 100 billion pounds on a new generation of Trident nuclear weapons.” Indeed, although the election was mostly dominated by the country’s sluggish economic recovery, the campaign also illustrated the tremendous polarization over the United Kingdom’s nuclear future.

The country has until 2016 to make a final decision on Trident, given the decade-plus lead time required to develop a replacement for the country’s four nuclear-armed submarines, which are set to expire in 2028. Although the governing Conservatives—who pledged to pursue a “like-for-like” replacement of Trident—will now return to Westminster with a stronger majority government, the election deprived the public of a proper debate over the merits of that plan.

Demonstrators take part in an anti-Trident rally in Glasgow, April 4, 2015.
Demonstrators take part in an anti-Trident rally in Glasgow, April 4, 2015. 
Russell Cheyne / Reuters
Instead, the issue became another locus for political sparring over fiscal responsibility. The Liberal Democrats, for instance, argued that the United Kingdom could maintain a credible deterrent with a cheaper alternative involving three, or perhaps fewer, submarines. Labour tried to straddle both positions, maintaining a commitment to the United Kingdom’s longstanding continuous at-sea-deterrence (CASD) policy through four submarines, but leaving open the possibility that strategic and technological imperatives could permit fewer boats at lower cost.

Despite the differences between the parties, the size and cost of a Trident replacement are difficult to contest. Experts are generally in agreement that, to keep its current level of deterrence, the United Kingdom needs four boats: one on active duty, one undergoing scheduled maintenance, one involved in training, and one in reserve. Any attempts to cut the number of vessels would save only a fraction of the program’s total price tag, while undermining the purpose of the entire enterprise by leaving the country without a credible deterrent for perhaps as much as a quarter of a year. And proposals for alternative delivery systems, including air- or sea-launched cruise missiles, would offer limited savings because they would require the United Kingdom to build indigenous warhead and missile capabilities. These new systems would also be more vulnerable to attack and would cover a shorter range than an updated Trident ballistic missile.

The debate over the size of the Trident replacement obfuscated a more demanding question: Nukes for what?

Conservative Prime Minister David Cameron argued that a Trident replacement is crucial for protecting against current and future threats. Others such as Nicola Sturgeon, who led her Scottish National Party to a landslide victory in Scotland, have argued that the country no longer needs a nuclear deterrent to protect its core national security interests. Sturgeon may be right. In fact, the debate over the future of Trident is less a matter of British security and instead about what the country is willing to pay to sustain its outsized role in the world.

The only thing the United Kingdom’s nuclear deterrent is good for is continued leverage and influence in global affairs.
The security justifications for an independent British nuclear capability are as numerous as they are unconvincing. The country’s nuclear arsenal was developed during a period of deep fear in Western Europe. During the 1950s, the nation’s leaders had little confidence in U.S. security guarantees—and, at the very least, thought that their Soviet adversaries shared this belief. They thus insisted that an independent nuclear capability was essential. Today, the country continues to enjoy deterrence through its membership in NATO; the additional benefits it gets from an independent capability are few, especially given that there are virtually no circumstances under which the United Kingdom would launch a nuclear missile without U.S. consent. Indeed, no contemporary threats to the United Kingdom’s territorial security—from terrorism to cyberespionage—are well met by a nuclear deterrent.

In truth, the only thing the United Kingdom’s nuclear deterrent is good for is continued leverage and influence in global affairs. The decision to maintain it thus rests on a single question, one that all of the major parties failed to meaningfully answer: What role does the United Kingdom want to play in the world?

In his memoir, former British Prime Minister Tony Blair wrote that “The expense [of Trident] is huge, and the utility in a post cold war world is less in terms of deterrence and non-existent in terms of military use.” But ultimately, he argues, relinquishing nuclear arms would result in "too big a downgrading of our status as a nation.” From the leader of a former colonial superpower, the pursuit of “status” might sound somewhat unseemly. But the point remains. In the face of declining markers of its relative power, a nuclear deterrent is a vital source of continued influence.

Today, the United Kingdom’s position in the world’s major international institutions reflects an outdated assessment of its power and capabilities. From its seat at the negotiating table with Iran to its role brokering peace talks in South Sudan, the country enjoys disproportionate influence in international politics, enabled by continued possession of a robust nuclear deterrent. It is not that the British can threaten nuclear punishment for those that don’t take it seriously, but they can point to their arsenal as a primary qualification for their seat in UN Security Council. Apart from nuclear weapons, the United Kingdom shares very little with its P5 peers in the way of most reasonable metrics of power, from total military spending to manpower to contributions to international organizations to economic might (of course, neither does France—perhaps one reason Paris is not considering ceding its nuclear arsenal).

Philip Hammond, then defense secretary and now secretary of state for foreign and commonwealth affairs, poses for a photograph in front of a Trident-equipped submarine, October 29, 2012.
Philip Hammond, then defense secretary and now secretary of state for foreign and commonwealth affairs, poses for a photograph in front of a Trident-equipped submarine, October 29, 2012.
Danny Lawson / Reuters
In the absence of nuclear weapons, the United Kingdom may still retain a legal claim to its permanent seat, but it is doubtful that it would retain the political capital to continue to punch above its declining economic and military weight. Indeed, a decision to abandon nuclear weapons is likely to undermine the legitimacy of the P5 and the Security Council itself. As the Security Council continues to come under fire for its under-inclusiveness, the prospect that a non-nuclear middle power might wield veto power over future decisions further undercuts confidence in the institution. The United Kingdom must work to sustain confidence in the capacity of the institution and its permanent members to address global security threats.

Nuclear weapons can serve as a useful insurance policy in a geopolitical future that is likely to be much less favorable to the United Kingdom.
Absent nuclear weapons, Britain would also find it harder to execute its international priorities. Whitehall considers nuclear disarmament to be a leading foreign policy objective. Ironically, the country is better positioned to push that agenda with a credible nuclear deterrent. The United Kingdom cannot influence the scope of future nuclear arms reductions if it unilaterally renounces its bargaining leverage. As former British Shadow Foreign Secretary Aneurin Bevan once argued, negotiating for disarmament after having relinquished nuclear weapons would amount to going “naked into the conference chamber.” 

Finally, nuclear weapons can serve as a useful insurance policy in a geopolitical future that is likely to be much less favorable to the United Kingdom. For one, renewing Trident may bolster British influence in a less stable Europe. Further, as the United States undertakes its strategic rebalancing toward Asia, Europe may be increasingly required to shoulder more of the burden for managing an irredentist Russia. The United Kingdom would have a much more constrained ability to negotiate effectively with its Russian counterparts in the absence of a credible deterrent. In fact, continued possession of nuclear weapons is important to Britain maintaining this sort of leverage today. As Russia confronts declining conventional military power in the face of heavy Western investment in precision-guided weaponry, it has turned increasingly to nuclear weapons to pursue its objectives. Moscow has explicitly threatened to use “nuclear force” to defend its annexation of Crimea.

Although many have wished away the post-Cold War relevance of nuclear deterrence, Russia’s actions suggest that it will have to play some role, even if the world’s understanding of deterrence needs to evolve to reflect new threats that involve significant asymmetry of interests. Russia’s turn to nuclear-based threats mean that NATO’s ability to influence Russian behavior is predicated at least partially on a credible, and thus Europe-based, deterrent. If the United Kingdom hopes to influence the scope of NATO’s response to Moscow it will need to demonstrate its own capacity to respond to implicit appeals to nuclear blackmail. A NATO that relinquishes part of its nuclear capability is likely to signal weakening resolve within the institution to its members’ commitment to common security and defense.

For these reasons, policymakers in Washington no doubt eagerly watched this month’s election. In an era of U.S. grand strategy that more firmly emphasizes multilateralism, British and American fates are tied. From the interventions in Afghanistan and Iraq to the efforts to thwart a nuclearizing Iran, the United Kingdom has arguably been the most stalwart supporter of U.S. foreign policy objectives. Thus while U.S. defense officials are almost certainly cheering the election result, some may still be holding their breath. The fractious electoral debate over Trident raises questions about how far the Conservatives are willing to go keep their promise if political pressure continues to mount as the country approaches the 2016 deadline. The decision will have significant implications. A United Kingdom with less influence over the world around it is not good news for Washington.  

To be sure, a denuclearized United Kingdom is not a country bereft of the power to shape the world. It is, however, a country with a much reduced ability to do so. The extent of the loss is certainly an open question, as is its cost in money. Whether the British public is willing to lay out over $150 billion—“the price,” Winston Churchill once said, “for sitting at the top table”—is and should be a major source of debate. There are clear tradeoffs at play. A Trident replacement could demand as much as one-third of Britain’s defense spending over the next ten years, which means fewer resources for conventional capabilities to address other national security threats and participate in future interventions. Indeed, the British Army is slated to shrink to its smallest size since the dawn of the nineteenth century, and the Royal Navy, as journalist Gideon Rachman recently argued, will soon become incapable of assembling “a task force of the size that Britain needed during the Falklands war.” More broadly, significant defense expenditures mean fewer resources to finance an ever-tightening social safety net. 

Perhaps with the election behind them, British leaders can drive a more civil and intelligent debate over the value of these important tradeoffs. It’s a conversation the country deserves and which it still has yet to have. 

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  • JOSEPH SINGH is a Rhodes Scholar and a graduate student at the University of Oxford’s Blavatnik School of Government.
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