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European Security

Week Ahead March 3-9: IAEA mtg; Pentagon Budget; Nuclear Security; Ukraine & the NPT

As the crisis in Ukraine continues to dominate global attention and the news headlines, several other arms control developments of significance in the coming week. For more news and analysis on these and other weapons-related security issues, consider subscribing to ACA's monthly journal Arms Control Today, which is available in print/digital and digital-only editions. The March issue of ACT will be available online later this week to all subscribers. - the Editors at Arms Control Today Week of March 3: IAEA Board of Governors Convenes The 35-member International Atomic Energy Agency (IAEA)...

The Week Ahead, Jan 27-Feb. 2: State of the Union

This bulletin highlights significant events in the world of arms control in the coming days, as compiled by staff and friends of the Arms Control Association. For more news and analysis on these and other weapons-related security issues, consider subscribing to ACA's monthly journal Arms Control Today . The entire January/February 2014 issue is now available online for all ACA members and digital subscribers. – the Editors at Arms Control Today IAEA Goes Underground Nuclear inspectors will visit Iran's Gchine uranium mine in coming days, according to Yukiya Amano, director general of the...

United States Lagging on New START Implementation

By Greg Thielmann The latest semi-annual exchange of data under the New Strategic Arms Reduction Treaty (New START) shows continuing U.S. lethargy in implementing the modest reductions agreed to when it joined Russia in signing the treaty three-and-a-half years ago. One should not over-read any change from one period to the next. Numerical spikes or dips can occur from such things as ballistic missile submarines entering or leaving overhaul or from already retired weapons finally being destroyed under the terms of the treaty and taken off the official rolls. Yet a clear picture of trends...

Trident Tribulations: Understanding the UK’s Trident Alternatives Review

The United Kingdom’s nuclear weapons policy is in flux. A UK decision to end continuous at-sea deterrence would be in keeping with the country’s self-identification...

Nick Ritchie

The United Kingdom’s nuclear weapons policy is in flux as the country debates whether to replace its current Trident strategic nuclear weapons system and remain in the nuclear weapons business for another generation.

Choices about nuclear weapons are certain to feature in the next general election in May 2015. The debate is deeply political and parochial, but also involves a much broader set of issues related to nuclear deterrence and steps toward nuclear disarmament. Some of this debate came to a head with the publication of the government’s “Trident Alternatives Review” in July.[1] This article examines the political issues surrounding the report and sets them in the broader context of deterrence and disarmament.

Current UK policy is to have a single Vanguard-class submarine on patrol somewhere in the Atlantic ready to fire as many as 40 highly accurate thermonuclear warheads on U.S.-designed and -built Trident II (D-5) ballistic missiles within days, or even hours, of a prime ministerial decision. (“Trident” technically refers to the missile, but the term is used in the UK to mean the entire system.) Four such submarines are based at the Faslane naval base in Scotland that enable the UK to have one permanently at sea in a posture called continuous at-sea deterrence.

The submarines were commissioned into service between 1994 and 2001 and will begin to reach the end of their service lives in the early 2020s. Trident is now the UK’s only nuclear weapons system after the country divested itself of gravity bombs, theater nuclear weapons, and forward-deployed U.S. nuclear weapons during the 1990s and 2000s. If the submarines are not replaced in some form, the UK will effectively cease to be a nuclear-weapon state.[2]

In 2006 the Labour government under Tony Blair gave the green light to a long, expensive, and controversial process of replacing the Trident system with a “like-for-like” capability starting with the procurement of a new fleet of ballistic missile submarines, then a new warhead, and a new U.S. missile much later still. A decision was needed at that time because a new submarine would take approximately 17 years to design and deploy.[3] In May 2010, the Labour government was voted out of office and replaced by a coalition government comprising Conservatives and Liberal Democrats, the latter as the junior party.

The Liberal Democrats had never accepted the case for a like-for-like replacement.[4] They have long argued that the UK no longer requires such a “fantastically expensive insurance policy”[5] procured in the depths of the Cold War to flatten Moscow and other major Russian cities or, to use more diplomatic language, “hold at risk key centres of Soviet state power.”[6] The world had moved on, and at a time of severe pressure on government spending, including the defense budget, it was surely right to question the logic of committing 25 billion pounds to a new fleet of submarines in this “age of austerity.”[7] Nevertheless, “unilateral nuclear disarmament” has become a pejorative term in Westminster politics ever since Labour’s sojourn in the political wilderness in the 1980s partly as a result of its electorally unpopular platform of relinquishing nuclear weapons. In 2005 the Liberal Democrat leadership began instead to make the case for a middle way: a smaller, cheaper nuclear weapons system more in keeping with the geopolitical realities of today’s complex conflicts.

Once in government, the Liberal Democrats successfully pushed back the main spending decision on the new submarines (the “main gate” decision, in Ministry of Defence jargon) from 2014 to 2016, which is after the next general election. The party also negotiated an agreement with the Conservatives to undertake a review to determine if the program was providing sufficient “value for money.” That assessment was part of the 2010 Strategic Defence and Security Review. The accord between the two parties also called for an in-depth, formal government study of alternatives to a like-for-like replacement of the Trident system.[8]

The Trident Alternatives Review

The alternatives review was initiated in May 2011, and after some delay, the report was published in July of this year. The document presents a hierarchy of nuclear postures at decreasing levels of operational readiness. The first two postures are the current “continuous deterrence” and “focussed deterrence,” the latter based on continuous deterrence for a specific period against a specific adversary. Absent a specific threat, the system would be maintained at “reduced readiness.” Three reduced readiness postures are outlined: “sustained deterrence,” “responsive deterrence,” and “preserved deterrence,” at progressively lower levels of readiness and ability to return to the higher levels.

The review then applies these postures to four delivery systems: the combination of a Trident ballistic missile with a missile-carrying submarine, a new cruise missile and warhead deployed aboard the UK’s new Astute-class attack submarines, a nuclear bomb or a stealthy or supersonic cruise missile for the F-35 Joint Strike Fighter the UK is procuring from the United States, and a stealthy cruise missile for a new large aircraft. The report concludes that “there are alternatives to Trident that would enable the UK to be capable of inflicting significant damage such that most potential adversaries around the world would be deterred.”[9]

The Liberal Democrats had initially championed the idea of arming Astute-class attack submarines, which currently are equipped to fire U.S. conventionally armed Tomahawk cruise missiles, with a new nuclear-tipped cruise missile. The report states, however, that this would be more expensive than replacing the Trident system on an equivalent basis because of the cost and time of developing a new cruise missile warhead—24 years, according to the report. This would exceed the service life of the current submarines and require building two new ballistic missile submarines to cover the gap until a new cruise missile could be deployed.

With that option no longer economically and politically viable, the Liberal Democrats now appear set to support a reduced version of the current system by ending the outdated requirement for continuous patrols, building two or three instead of four new submarines, further reducing the stockpile of missiles and warheads, and perhaps exploring the possibility of using the submarines in roles beyond a dedicated nuclear mission. Ending continuous patrols would also ease pressure on overstretched submarine crews and alleviate ongoing problems in recruitment and retention. In fact, a variant of the current Trident system represents the path of least technical, financial, and political resistance in any discussion of alternatives.[10] The Liberal Democrats debated their defense and nuclear policies for their 2015 general election manifesto at their party conference in September in Glasgow—an interesting choice given the anti-Trident sentiment of the Scottish electorate—and passed the leadership’s motion to support this policy.[11]

Conservative Party leaders remain committed to nuclear business as usual. They insist it is essential to continuously deploy a very sophisticated nuclear capability of global reach aboard a fleet of dedicated submarines.[12] Anything less than such “essential protection” risks fatally undermining the nation’s security, they argue.[13] The Conservatives will use the report to delegitimize a middle way as dangerous, naive, or incompetent in favor of their preferred default position.[14]

The big political question is how Labour will respond. When Ed Miliband was elected leader of the party, he said the UK now needs “to look very carefully at whether renewing Trident is the necessary or the right thing to do.”[15] There is now an active debate. Some former defense secretaries in the party, such as George Robertson and John Hutton, are firmly in favor of a like-for-like replacement. Others, such as Des Browne, are in favor of dropping continuous at-sea deterrence but still retaining nuclear weapons. Former Chief Whip Nick Brown and many backbenchers support relinquishing nuclear weapons altogether.[16]

Miliband confirmed at the party conference in October 2012 that Labour’s policy on Trident replacement would be revisited after the publication of the alternatives report and another report by the British American Security Information Council’s Trident Commission. The commission is an independent cross-party body established in 2011 to review UK nuclear weapons policy and led by Browne (now a Labour peer in the House of Lords) and two current members of Parliament, Malcolm Rifkind (Conservative) and Menzies Campbell (Liberal Democrat).[17] With the former report now published and the latter due in early 2014, Miliband will face a difficult choice: stick with the Blair and Tory plan of like-for-like replacement or pursue an alternative nuclear posture.

Minimum Deterrence

There is more at stake in the Trident debate than domestic electoral positioning. Anything other than a direct like-for-like replacement of the current system will mean rethinking the commitment to continuous at-sea deterrence. This, in turn, means rethinking conceptions of what constitutes a credible and effective minimum deterrent threat and could have wider ramifications.

A Spectrum of Nuclear Deterrence

There are a number of conceptions of nuclear deterrence, differing in elements such as force size, posture, and adversarial context. These conceptions can be seen as existing on a spectrum whose contours can be sketched from the nuclear histories of nuclear-armed states.

At one end lies the maximum deterrence practiced by the United States during the Cold War. This version based effective, credible deterrence on nuclear superiority over the Soviet Union, using a range of nuclear forces from nuclear shells for frontline troops to helicopter-borne nuclear depth bombs. The next step along the spectrum moves toward current conceptions of Chinese, French, and UK minimum deterrence. These involve warheads numbers in the low hundreds, a general rejection of nuclear weapons as war-fighting tools, and a limited number of roles for nuclear weapons.[1] Further down the spectrum, one encounters the so-called recessed form of nuclear deterrence practiced by India through the 1980s and 1990s based on nonweaponization of its nascent nuclear weapons capability. This approach was judged to exert a sufficient deterrent effect on Pakistan based on the mere possibility that major aggression could result in a nuclear encounter.[2]

Moving further along the spectrum, one goes from nondeployment to nonproduction of nuclear weapons. A “virtual” deterrent effect is exerted at this point through a proven but disassembled nuclear arsenal capable of reconstitution and redeployment within a specific time frame.[3] Further yet, the spectrum reaches the notion of weaponless deterrence, which envisages zero nuclear weapons or components but a residual military nuclear industrial base that could, over time, generate or regenerate a basic deliverable nuclear capability.[4]


1. See Li Bin, “China’s Potential to Contribute to Multilateral Nuclear Disarmament,” Arms Control Today, March 2011.

2. See George Perkovich, “Trip Report: Pakistan and India,” September 10-12, 1992, pp. 5-6.

3. Michael Mazarr, ‘The Notion of Virtual Arsenals,” in Nuclear Weapons in a Transformed World: The Challenge of Virtual Nuclear Arsenals, ed. Michael Mazarr (New York: St. Martin’s Press, 1997).

4. Jonathan Schell, The Abolition­ (London: Picador, 1984).

    UK nuclear weapons policy has long been characterized as one of minimum deterrence. The country has a comparatively small nuclear arsenal that is restricted to a single delivery system for strategic, as opposed to war-fighting, purposes. In addition, the UK has established a series of declaratory constraints on the circumstances in which it would consider using or threatening to use its nuclear weapons.

    The prevailing wisdom in London is that a credible and effective threat requires an assured capability to retaliate against a strategic attack in any and all conceivable circumstances. Because no one has a crystal ball, this argument runs, there is no guarantee that the UK never will face a direct threat that could be countered only through an assurance of nuclear retaliation. Therefore, the UK should retain its current capability, just in case. Any sign of vulnerability, any chink in the nuclear armor, could have catastrophic consequences in a crisis.[18]

    This translates into a requirement for highly accurate ballistic missiles of global reach capable of delivering dozens of thermonuclear warheads from a nuclear delivery platform on continuous alert that is invulnerable to a “bolt from the blue” first strike.[19] If the UK government still considers it essential to permanently deploy strategic nuclear weapons on alert at sea, then keeping the current arrangement is the obvious choice, particularly given the cost efficiencies and risk reduction that come with being embedded in a much bigger U.S. Trident program.

    This orthodoxy, however, has been challenged in the current debate. Skepticism abounds as to the strategic necessity of maintaining the current nuclear posture. When Trident was originally procured in the early 1980s, Defence Secretary John Nott said its purpose was to provide “an ultimate defence of this country against a nuclear strike, a pre-emptive strike by a nuclear power.”[20] The only country that can deliver such an attack against the UK now and for the foreseeable future is Russia.

    Yet, it is widely and officially acknowledged that the Cold War is truly over and that the possibility of a surprise Russian nuclear first-strike is so low as to be near zero.[21] Indeed the UK government acknowledges that the country faces no major, direct nuclear threat and has not since the early 1990s when it stopped targeting its nuclear weapons at Russia on a day-to-day basis.[22] That is about one-third of the time that the UK, which first tested a nuclear weapon in 1952, has been a nuclear-weapon state.

    Adherents of the nuclear orthodoxy see an ongoing requirement to maintain strategic nuclear weapons on permanent high alert as an ultimate “insurance” against existential military threats to the state. Inescapable uncertainty creates an enduring need for strategic nuclear weapons, advocates of this view argue. Yet for many in the UK, the strategic security case does not add up.

    This has led many to question the necessity of the Trident system and the continuous at-sea deterrence posture and to explore a range of alternative nuclear postures and systems that open up when these requirements are dropped. In fact, the alternatives review was established to push the envelope of what constitutes a credible capability at varying degrees of readiness below continuous at-sea deterrence.[23] This requires a different conception of credibility that says an effective nuclear deterrent threat does not require 100 percent certainty of retaliation. Instead, the very presence of nuclear weapons in a country under attack or threatened with attack, together with the uncertainty of total success in any pre-emptive attack, will induce sufficient caution into adversarial relations if one believes in the logic of nuclear deterrence at all.[24] This view of nuclear deterrence argues that as long as a country has a proven ability to deploy nuclear weapons, the size of the stockpile and the ability to deliver them against an adversary are of secondary concern.

    The fundamental core of nuclear deterrence lies in the possession of the weapons. Shai Feldman, a scholar of nuclear weapons and the Middle East, has concluded that Saddam Hussein “probably” was deterred from attacking Israel with ballistic missiles armed with chemical warheads in 1991 “not by the certainty that Israel would retaliate with nuclear weapons, but rather by his inability to rule out this possibility.”[25] This supports the observation in 2006 by Michael Quinlan, former UK permanent undersecretary of state in the Ministry of Defence, that “[e]ven a modest chance of a huge penalty can have great deterrent force,”[26] assuming, of course, an aggressor is deterrable.

    One therefore can think of nuclear deterrence not as an either/or dichotomy (either do deterrence this way or have zero deterrent effect) but as a spectrum. The debate over the Trident review has opened up the possibility of shifting UK ideas of minimum deterrence further along that spectrum (see box).

    This challenges the idea of an objective set of criteria for nuclear deterrence and instead more accurately characterizes it as a subjective political assessment. It is worth noting two things in this regard. First, ending continuous at-sea deterrence is not a new or outrageous idea. In the current debate, Browne, former Chief of the Defence Staff Charles Guthrie, former Foreign Secretary David Owen, and Quinlan all have questioned the strategic necessity of continuous at-sea deterrence.[27] Second, many of the criteria for minimum deterrence are defined by the capabilities of the current Trident II missile system, which was procured from the United States in the early 1980s, rather than deduced from an abstract theory of nuclear deterrence.[28]

    A UK decision to end continuous at-sea deterrence and move the country’s collective notion of minimum deterrence a notch or two down the spectrum would have implications beyond the country’s borders. Pressure for serious progress toward nuclear disarmament is increasing as non-nuclear-weapon states become ever more frustrated with slow progress by the nuclear-weapon states toward nuclear disarmament as one review after another for the nuclear Nonproliferation Treaty (NPT) rolls by.[29] The non-nuclear-weapon states are looking for significant steps that will radically devalue nuclear weapons in the security policies of the weapon states.[30]

    This means qualitative changes in prevailing nuclear doctrine as an essential component of a nuclear disarmament process and indicator of the nuclear-weapon states’ commitment to that goal alongside quantitative changes in nuclear numbers. The non-nuclear-weapon states elicited such a commitment at the 2010 NPT Review Conference when, in the meeting’s final document, the treaty parties formally agreed “[t]o further diminish the role and significance of nuclear weapons in all military and security concepts, doctrines and policies” as part of a 64-point action plan.[31]

    Reducing the readiness of nuclear forces, or de-alerting, is part of a package of measures long advocated by non-nuclear-weapon states to diminish the role of nuclear weapons. Ending continuous at-sea deterrence in the UK and adopting a “reduced readiness” posture would constitute an important qualitative change in nuclear posture and a crucial next step in reducing the value of nuclear weapons.

    Such a move would be in keeping with the UK’s self-identification as the most forward leaning of the nuclear-weapon states on nuclear disarmament. London has taken a number of important steps to reduce the size of its nuclear arsenal and increase transparency of its production of fissile materials and warhead numbers. It has modified its declaratory policy by further restricting the circumstances under which it might consider using nuclear weapons. It has ended nuclear testing, ratified the Comprehensive Test Ban Treaty, ended production of fissile materials for use in nuclear weapons, and declared its full commitment to a nuclear-weapon-free world and supported a number of initiatives toward that end.

    An opportunity now exists for the UK to continue on this trajectory and demonstrate international leadership in new ways. In particular, it could take concrete steps to further diminish the salience of UK nuclear weapons in national security policy by reducing the size and operational readiness of its nuclear arsenal. This is eminently plausible in an era of negligible military threats to the survival of the UK. Furthermore, none of the main political parties in Westminster are advocating UK nuclear disarmament. The current debate over the alternatives review is about the more limited aim of rethinking nuclear deterrence with a view to reducing the salience of these weapons while retaining the capability to deploy them within a specific period of time should a major military threat to the survival of the state ever re-emerge.

    Additional constraints on UK nuclear weapons policy could set important precedents for progress toward complete nuclear disarmament by establishing new norms of deterrence doctrine and practice for one of the five original nuclear-weapon states and one of the three depositary states of the NPT. Such a move would clearly indicate that the UK no longer sees a compelling reason to deploy nuclear weapons for immediate use but is temporarily retaining them, pending their global elimination.

    A posture that abandons continuous at-sea deterrence would all but eliminate any intention to use nuclear weapons first in a crisis. Such a posture would reinforce political and legal commitments to non-nuclear-weapon states and provide a degree of strategic reassurance to other possessors of nuclear weapons that the UK is confident that it is not going to face a nuclear attack and therefore can scale back its reliance on nuclear weapons. It would signify an important “de-coupling”[32] of nuclear weapons from the broad, day-to-day calculus of national security by demonstrating that the UK is prepared to learn to live without nuclear weapons operationally deployed at sea on a permanent basis as a precursor to learning to live without nuclear weapons at all.



    Nick Ritchie is a lecturer in international security at the University of York in the United Kingdom. This article draws on themes developed in his book A Nuclear Weapons-Free World? Britain, Trident, and the Challenges Ahead (2012).




    1. UK Cabinet Office, “Trident Alternatives Review,” July 16, 2013, https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/212745/20130716_Trident_Alternatives_Study.pdf.

    2. For an overview, see Nick Ritchie, A Nuclear Weapons-Free World? Britain, Trident and the Challenges Ahead (London: Palgrave, 2012), ch. 1.

    3. For the government’s case in detail, see UK Ministry of Defence and UK Foreign and Commonwealth Office, “The Future of the United Kingdom’s Nuclear Deterrent,” December 2006.

    4. “Policy Options for the Future of the United Kingdom’s Nuclear Weapons,” 2010, http://www.libdems.org.uk/siteFiles/resources/docs/News/MCTrident%20Review.pdf.

    5. Nick Hopkins, “Trident Replacement Plans Are Based on Outdated Ideas, Says Former Minister,” The Guardian, April 22, 2013 (citing Nick Harvey, member of Parliament for the Liberal Democrat party, then minister for armed forces in the Ministry of Defence).

    6. David Owen, Nuclear Papers (Liverpool: Liverpool University Press, 2009), p. 48 (quoting Michael Quinlan, “The Future United Kingdom Strategic Nuclear Deterrent Force,” Defence Open Government Document 80/23, July 1980).

    7. Many figures have been cited in relation to the Trident replacement program. The government stated in 2011 that the projected capital cost of the “successor” submarines (not the warheads, missiles, or new infrastructure) is 25 billion pounds (at the time of spending). See UK Ministry of Defence, “The United Kingdom’s Future Nuclear Deterrent: The Submarine Initial Gate Parliamentary Report,” 2011, p. 10.

    8. For the rescheduling of the submarine program and results of the value-for-money review, see UK Government, “Securing Britain in an Age of Uncertainty: The Strategic Defence and Security Review,” Cm 7948 (2010), http://www.direct.gov.uk/prod_consum_dg/groups/dg_digitalassets/@dg/@en/documents/digitalasset/dg_191639.pdf.

    9. UK Cabinet Office, “Trident Alternatives Review,” p. 10.

    10. Nick Ritchie, “Stepping Down the Nuclear Ladder: Options for Trident on a Path to Zero,” Bradford Disarmament Research Centre Briefing Paper, No. 5 (May 2009), http://www.york.ac.uk/media/politics/documents/research/Trident_Options.pdf.

    11. Nigel Morris, “Lib Dem Conference: Members Back Nuclear Deterrent Alternative to Trident,” The Independent, September 17, 2013; Danny Alexander, “On Trident, We’re Still Fighting the Cold War,” The Independent on Sunday, July 21, 2013.

    12. Philip Hammond, “The Alternatives to Trident Carry an Enormous Risk,” The Telegraph, February 2, 2013.

    13. Ibid.

    14. David Cameron, “We Need a Nuclear Deterrent More Than Ever,” The Daily Telegraph, April 3, 2013.

    15. Andrew Grice, “Lib Dems Push for ‘Stand-by’ Trident Replacement Deal,” The Independent, July 19, 2012.

    16. George Robertson and John Hutton, “There Is No Magic Alternative to Trident—Britain Has Got to Keep It,” The Telegraph, February 28, 2013; Des Browne and Ian Kearns, “Trident Is No Longer Key to Britain’s Security,” The Daily Telegraph, February 5, 2013; Nick Brown, “Dropping Trident Will Lead to a Richer, Safer Britain,” New Statesman, June 21, 2012.

    17. “Miliband Trident Review Stance Welcomed,” DefenceManagement.com, October 4, 2012, http://www.defencemanagement.com/news_story.asp?id=21058. For details of the BASIC Trident Commission, see http://www.basicint.org/tridentcommission/.

    18. See UK Ministry of Defence and UK Foreign and Commonwealth Office, “The Future of the United Kingdom’s Nuclear Deterrent,” pp. 22, 27 (box 5-2).

    19. Frank Miller, “The Future of the United Kingdom’s Nuclear Deterrent,” RUSI Journal, Vol. 155, No. 2 (2010): 34-39.

    20. UK House of Commons Defence Committee, “Strategic Nuclear Weapons Policy,” HC 266 (1982), p. 21.

    21. “Joint Declaration by the President of the Russian Federation and the Prime Minister of the United Kingdom of Great Britain and Northern Ireland,” Moscow, February 15, 1994.

    22. See UK Ministry of Defence, “Strategic Defence Review,” Cm 3999 (1998), para. 23; UK Cabinet Office, “National Security Strategy of the United Kingdom,” Cm 7590 (2009), p. 65.

    23. For the review’s terms of reference, see http://data.parliament.uk/DepositedPapers/Files/DEP2011-0825/DEP2011-0825.zip (file containing Trident Alternatives Review terms of reference).

    24. For further information, see Nick Ritchie and Paul Ingram, “A Progressive Nuclear Policy: Rethinking Continuous-at-Sea Deterrence,” RUSI Journal, Vol. 155, No. 2 (2010), pp. 40-45.

    25. Shai Feldman, “Middle East Nuclear Stability: The State of the Region and the State of the Debate,” Journal of International Affairs, Vol. 49, No. 1 (1995), p. 217.

    26. Michael Quinlan, “Deterrence and Deterrability,” in Deterrence and the New Global Security Environment, ed. Ian R. Kenyon and John Simpson (London: Routledge, 2006), p. 5.

    27. UK House of Lords, Official Report, March 26, 2009, col. 806 (Guthrie); Owen, Nuclear Papers, p. 13; Browne and Kearns, “Trident Is No Longer Key to Britain’s Security”; Michael Quinlan, “The Future of United Kingdom Nuclear Weapons,” International Affairs, Vol. 82, No. 4 (2006), p. 636.

    28. Michael Quinlan, permanent undersecretary at the Ministry of Defence at the time of Trident procurement, wrote in 2004,

    Purely in weight of strike potential, the United Kingdom could have been content with less than Trident could offer, even in C4 version originally chosen (let alone D5 version to which the United Kingdom switched in early 1982, when it had become clear that the United States was committed to proceed with its acquisition and deployment). The original choice and the switch were driven in large measure by the long-term financial and logistic benefits of commonality with the United States. After the end of the Cold War, the United Kingdom announced a series of discretionary reductions in warhead load to well below what Trident was capable of carrying.

    Michael Quinlan, “The British Experience,” in Getting MAD: Nuclear Mutual Assured Destruction, Its Origins and Practice, ed. Henry D. Sokolski (Carlisle, PA: Strategic Studies Institute, November 2004), p. 271.

    29. Nick Ritchie, “Waiting for Kant: Deterrence, Devaluing, and Delegitimising Nuclear Weapons” (paper presented at the ISA Annual Conference, San Francisco, April 2013).

    30. Nick Ritchie, “Valuing and Devaluing Nuclear Weapons,” Contemporary Security Policy, Vol. 34, No. 1 (2013): 146-173.

    31. 2010 Review Conference of States Parties to the Treaty of the Non-Proliferation of Nuclear Weapons, “Final Document,” NPT/CONF.2010/50 (Vol. I), 2010, p. 21.

    32. Michael Mazarr, “Nuclear Doctrine and Virtual Nuclear Arsenals,” in Nuclear Weapons in a Transformed World: The Challenge of Virtual Nuclear Arsenals, ed. Michael Mazarr (New York: St. Martin’s Press, 1997), p. 47.

    Posted: October 2, 2013

    UK Review Doubts Trident Alternatives

    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.

    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.

    Posted: September 4, 2013

    Limited Test Ban Treaty Turns 50

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    Senate Scales Back the B61

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    Arms Control and Proliferation Profile: France

    April 2017


    Updated: April 2017

    As a nuclear-weapons state under the NPT, France maintains the world’s third largest nuclear arsenal, estimated to include 300 nuclear warheads. Since it eliminated its land-based ICBMs beginning in 1996, 80 percent of these warheads are designed for delivery through SLBMs, with the remainder affixed to ALCMs carried by strategic bombers. France has taken significant steps toward disarmament—including halving its warhead total since its Cold War peak, no longer deploying nuclear weapons on its aircraft carrier, the Charles de Gaulle, and extending the time it takes to launch nuclear weapons to several days—and it adheres to a principle of “strict sufficiency” whereby it keeps its nuclear arsenal at the lowest possible level in accordance with the strategic context.


    Major Multilateral Arms Control Agreements and Treaties

    Export Control Regimes, Nonproliferation Initiatives, and Safeguards

    Nuclear Weapons Programs, Policies, and Practices

    • The Nuclear Arsenal, an Overview
    • Delivery Systems
    • Ballistic Missile Defense Systems
    • Fissile Material
    • Proliferation Record
    • Nuclear Doctrine

    Biological Weapons

    Chemical Weapons

    Other Arms Control and Nonproliferation Activities

    • Open Skies Treaty
    • Conference on Disarmament (CD)
    • Nuclear Weapons Free Zones
    • Nuclear Security Summits
    • Joint Comprehensive Plan of Action (JCPOA)

    Major Multilateral Arms Control Agreements and Treaties




    Nuclear Nonproliferation Treaty



    Comprehensive Test Ban Treaty



    Convention on the Physical Protection of Nuclear Material (CPPNM)



    CPPNM 2005 Amendment



    Chemical Weapons Convention



    Biological Weapons Convention



    International Convention for the Suppression of Acts of Nuclear Terrorism



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    Export Control Regimes, Nonproliferation Initiatives, and Safeguards



    Australia Group


    Missile Technology Control Regime


    Nuclear Suppliers Group


    Wassenaar Arrangement


    International Atomic Energy Agency (IAEA) Additional Protocol

    Signatory, entered into force in April 2004

    Global Initiative to Combat Nuclear Terrorism


    Hague Code of Conduct against Ballistic Missile Proliferation


    Proliferation Security Initiative


    UN Security Council Resolutions 1540 and 1673

    France has filed reports on its activities to fulfill the resolutions and volunteered to provide assistance to other states

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    Nuclear Weapons Programs, Policies, and Practices

    The Nuclear Arsenal, an Overview
    France maintains the third largest nuclear weapons force in the world. As of 2017, France is estimated to possess approximately 300 nuclear warheads, most of which are designed for delivery by submarine-launched ballistic missiles (SLBMs) with the remainder affixed to air-launched cruise missiles (ALCMs) carried by strategic bombers.

    French President François Hollande publically affirmed the size of the arsenal in February of 2015, when he said that France’s stockpile included 300 warheads for 48 SLBMs and 54 cruise missiles. Estimates place France’s deployed strategic warhead numbers at around 290, with a remaining 10 in reserve.  Although France has reduced the size of its nuclear arsenal by half its Cold War numbers, the current stockpile has remained relatively stable over the last few decades. In 2008, former French President Nicolas Sarkozy stated that France’s arsenal would be reduced below 300 warheads but also reaffirmed France’s commitment to its nuclear deterrent, declaring it as a “life-insurance policy.”

    In 2009, France declared that its aircraft carrier, the nuclear-powered Charles de Gaulle, no longer deployed nuclear weapons, marking the end of peacetime deployments of short-range nuclear weapons at sea. France continues to modernize its nuclear arsenal and develop new missiles. According to the French Ministry of Defense (MoD), the nuclear deterrence budget in 2016 was 3.6 billion euros.  

    Delivery Systems

    Intercontinental Ballistic Missiles (ICBM)

    • In 1996, France decided to eliminate its nuclear-armed land-based ballistic missiles.

    Submarines and Submarine-Launched Ballistic Missile (SLBM)

    • France’s nuclear submarine force consists of 4 Triomphant- class nuclear-powered ballistic missile submarines (SSBNs) known as the FOST (La Force Océanique Stratégique).This fleet forms the backbone of the France’s nuclear deterrence and is responsible for approximately 80 percent of its nuclear arsenal. It is based at the Île Longue peninsula, south of Brest in the Brittany region of France.
    • At least one submarine remains out at sea at all times on deterrent patrol while another two remain fully operational and can be rapidly put to sea. The fourth submarine, as per the Triomphant-class’ extensive maintenance cycle, will be undergoing overhaul at any given time; as a result, France only maintains three sets of SLBMs and warheads.  
    • Beginning in 2010 with the Vigilant, two of the SSBNs have been upgraded to carry the M51.1 missile while the remaining two are to be upgraded with the M51.2 missile. All four SSBNs are expected to be upgraded with M51 missiles by 2019. The M51.3 is anticipated to be deployed on the Terrible in 2020.
    • In 2013, France was beginning preliminary work for the development of a third generation SSBN to replace the Triomphant-class by 2030.   


    • France fields 2 types of SLBMs:
      • M45 – 16 missiles carrying around 80 warheads, each missile can carry a total of six 100 kt TN-75 multiple independently targetable reentry vehicle (MIRV) warheads, 4,000-6,000 km range. The M45, deployed in 1997, is an improved version of the M-4 missile, its predecessor.
      • M51.1 – 32 missiles carrying around 160 warheads, each missile can carry a total of six 100 kt TN-75 MIRVs, 6,000+ km range. With greater range and accuracy, the M51.1 was developed in 2010 to replace the ageing M45 missiles; replacement is still in progress as of 2017.
      • M51.2 – an unspecified number of missiles and warheads, capable of carrying up to six new 150 kt TN MIRVs, 6,000+ km range. Develepment of the M51.2 is ongoing; a test of the missile failed in 2013.
      • M51.3 – in 2014, Airbus was contracted by the French government (now a joint venture between Airbus and Safran) to produce a new generation M51 missile, the M51.3. Details are unknown but it is expected to be tipped with the TNO (tête nucléare océanique) warhead and enter service in 2020 and to arm the successor to the Triomphant-class SSBN.
    • French SLBMs do not carry the maximum number of nuclear warheads. Former President Jacques Chirac stated in 2006, that "The number of nuclear warheads has been reduced in certain of the missiles in our submarines." This decision was supposedly made to improve targeting flexibility against regional powers.  

    Strategic Bombers

    • The French Air Force currently operates Mirage 2000N and Rafale aircrafts which are capable of carrying and delivering nuclear payloads.
    • According to a French MoD “Defense Key Figures” report in 2016, the French Air Force possesses 23 Mirage 2000N nuclear and conventional assault planes and a further 81 Rafale omnirole aircraft. Of these, France deploys only around 20 nuclear-capable Mirage 2000Ns (though some sources cite 23) and 20 nuclear-capable land-based Rafale F3 aircraft.
    • Each of these planes carries a single 300 kt TNA warhead on an Air-Sol Moyenne Portée (ASMP) ALCM. The ASMP has a range of around 300 km or 500 km for the ASMP-A, an improved variant carried by most of the bombers.
    • By 2018, all of the Mirage 2000N fighters will be replaced by the Rafale fighters, completing the ongoing upgrading process.
    • The French Navy also operates 10 new nuclear-capable Rafale MF3 fighters that have replaced its Super Éntendard aircrafts, retired in 2016, that were also capable of carrying and delivering nuclear payloads. These aircraft also carry a single 300 kt TNA warhead fired from an ASMPA-A missile.

    Ballistic Missile Defense Systems

    France is part of the European Phased Adaptive Approach (EPAA), a collective missile defense system operated by NATO allies. To learn more, see: "The European Phased Adaptive Approach at a Glance."

    Fissile Material

    Highly Enriched Uranium (HEU)

    • After ending its production of HEU in June 1996, President Jacques Chirac announced in February 1996 that France no longer produced fissile material for weapons purposes and that would it would dismantle its fissile material production facilities.
    • As of 2016 estimates, France is believed to possess an HEU stockpile of around 31± 6 metric tons.
    • France holds approximately 26 ± 6 metric tons of military HEU. There exists significant uncertainty over this figure due to a lack of public information about French HEU production.
    • As of December 2014, France had declared a 4.6 metric ton stockpile of civilian HEU to the International Atomic Energy Agency (IAEA). A large percentage of this civilian stock is believed to be of U.S. and Russian origin for use in research-reactor fuel.


    • France ceased its production of separated plutonium in 1992.
    • As of 2016, France is estimated to possess a military plutonium stockpile of 6±1 metric tons.
    • At the end of 2014, France reported holding 61.9 tons of domestic unirradiated plutonium, the second largest stockpile globally, and 16.9 metric tons of reprocessed foreign unirradiated plutonium, mostly belonging to Japan.
    • France is one of the few countries that continues to reprocess spent nuclear fuel, and it accepts fuel from foreign countries for that purpose. Its AREVA La Hague plant has a commercial reprocessing capacity of about 1,700 tons of used nuclear fuel per annum (around half of the world’s light water reactor fuel reprocessing capacity as of 2009).  France uses separated plutonium to fabricate mixed oxide (MOX) fuel that is used in light water reactors.

     Proliferation Record

    • France officially maintains a long-standing position in support of nonproliferation activities.
    • In 1957, France signed a major nuclear cooperation agreement with Israel even though it was generally understood that Israel was interested in potentially developing a nuclear arsenal. France halted the agreement in 1960.
    • France built the Osirak reactor in Iraq despite warnings from other governments that the reactor might be used to support a secret Iraqi nuclear weapons program. Paris declined to rebuild the reactor after Israel bombed the plant in 1981.
    • France remains among the world’s top suppliers of peaceful nuclear facilities and expertise.

    Nuclear Doctrine

    French nuclear policy is one of calculated ambiguity regarding first-use of nuclear weapons.  France adheres to its principle of “strict sufficiency” whereby it keeps its nuclear arsenal at the lowest possible level in accordance with the strategic context. In its 2013 White Paper on Defence and National Security, France claims that its deterrence strategy is strictly defensive and that “The use of nuclear weapons would only be conceivable in extreme circumstances of legitimate self-defense” and that nuclear deterrence “protects France from any State-led aggression against its vital interests, of whatever origin and in whatever form” including terrorism. France has reaffirmed a 1995 negative security assurance to the UN not to use nuclear weapons against non-nuclear-weapon states-parties to the nuclear Nonproliferation Treaty (NPT) unless it is facing an invasion or sustained attack against its territories, armed forces, or states with which it has security agreement and the attack is in alliance with a nuclear-weapon state.

    Paris declared that it took steps in 1992 and 1996 to extend the time it takes to launch nuclear weapons. It is believed that France needs several days in order to launch nuclear weapons.


    France conducted 210 nuclear tests. The first test occurred Feb.13, 1960, and the last test took place Jan. 27, 1996. France was the fourth country to conduct a nuclear weapon test.

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    Biological Weapons

    • Little is known about past French biological weapons activities, which reportedly included research on anthrax, botulinum toxin, cholera, ricin, rinderpest, and salmonella.
    • France is not suspected of having a current offensive biological weapons program, and under France’s 1972 Law on the Prohibition of Biological Weapons, it is illegal to produce or stockpile these weapons. They are believed to have stopped their program after WWII.
    • France’s 2004 Code of Defense states that “The development, production, possession, stockpiling, acquisition, and transfer of microbiological agents, other biological agents and biological toxins, whatever their origin and mode of production, which are of a kind and quantity not suited for prophylactic, protection or other pacific purposes, are prohibited.”
    • France acceded to the Biological Weapons Convention (BWC) on Sep. 27, 1984, and is also member of the Australia Group.
    • France annually submits reports as confidence-building measures under the BWC and encourages other states to follow suit. It also hosts the annual plenary meeting of the Australia Group.
    • France maintains a biodefense program that it claims is in strict compliance with the BWC.

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    Chemical Weapons

    • During World War I, France produced and used mustard gas and phosgene. France maintained stockpiles of these weapons at the beginning of World War II but did not use them.
    • After World War II, France resumed offensive chemical weapons research and testing, and in the 1960s they manufactured Sarin and VX nerve agents.
    • France destroyed its stockpiles of chemical weapons prior to 1988. President François Mitterrand claimed, in a 1988 speech to the United Nations, that France no longer had any chemical weapons and ended production.
    • France signed the Chemical Weapons Convention (CWC) in Paris in 1993 and ratified it in 1995. It also holds that it displays “exemplary” cooperation with the Organisation for the Prohibition of Chemical Weapons (OPCW).

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    Other Arms Control and Nonproliferation Activities

    Open Skies Treaty
    France is a state-party to the Open Skies Treaty, which enables unarmed reconnaissance flights over all states-parties territories.

    Conference on Disarmament (CD)      
    The CD was formed in 1979 as a multilateral disarmament negotiation forum for the international community. France has regularly participated in its meetings. On April 9th, 2015, France formally deposited a draft fissile material cutoff treaty at the CD. 

    Nuclear Weapons Free Zones
    France has signed and ratified additional protocols pledging not to use or threaten to use nuclear weapons against any of the contracting parties to the African, Central Asian, Latin American and Caribbean, and South Pacific nuclear weapons free zone treaties. However, France maintains reservations to each of these protocols. No states have signed or ratified the Southeast Asian nuclear weapons free zone treaty protocol.

    Nuclear Security Summits
    In keeping with its official stance in support of securing nuclear material around the world, France has  participated in the 2010 Nuclear Security Summit (NSS) held in Washington, DC, the 2012 NSS held in Seoul, the 2014 NSS Held in The Hague, and the 2016 NSS held again in Washington, DC.

    Joint Comprehensive Plan of Action (JCPOA)
    Since its initiation of nuclear talks with Iran in 2003, France has engaged in multilateral diplomacy with Tehran over its nuclear program, including the 2015 Joint Comprehensive Plan of Action. After its conclusion, French Foreign Minister Laurent Fabius said that the deal would be sufficiently “robust” for another 10 years.

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    Posted: March 21, 2013


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