The United Kingdom and Nuclear Deterrence

Jeremy Stocker

• Publisher: Routledge
• Year: 2013
• ISBN:
  9781134974689
• Edition: 1
• Topic: History
• Subtopic: Military & Maritime History
• Index: History

In December 2003 the British government announced that within a few years it would need to take decisions about the future of Britain's strategic nuclear deterrent. Exactly three years later, its plans were revealed in a White Paper. The existing Trident system is to be given a life-extension, which includes building new submarines to carry the missiles, costing £15–20 billion. Britain has a substantial nuclear legacy, having owned nuclear weapons for over half a century. The strategic context for the deterrent has changed completely with the end of the Cold War, but nuclear weapons retain much of their salience. This Adelphi Paper argues that it makes sense to remain a nuclear power in an uncertain and nuclear-armed world. Given that deterrence needs are now less acute, but more complex than in the past, the paper asserts that deterrence also needs to be aligned with non-proliferation policies, which seek to reduce the scale of threats that need to be deterred. Somewhat overlooked in current policy are appropriate measures of defence, which can raise the nuclear threshold and, if required, mitigate the effects of deterrence failure. It concludes that the government's decisions about the future form of the deterrent are very sensible, but cautions that they still need to be integrated into a broader policy that embraces diplomacy, deterrence and defence to counter the risks posed by nuclear proliferation.

Chapter One
A Nuclear Legacy

On 3 October 1952 Britain detonated its first atomic device and became the world's third nuclear-weapon power. Britain was actually the first country seriously to investigate the possibility of producing an atomic weapon utilising the enormous power of nuclear fission.¹ The Maud Committee, set up in April 1940, reported the following year and initiated a research and development programme which was soon, however, subsumed into the larger Anglo-American Manhattan Project.²

Wartime cooperation was ended in 1946 when the US Congress passed Senator Brien McMahon's Atomic Energy Act, largely in ignorance of the extent of Britain's contribution to the Manhattan Project. In January 1947, a small Cabinet committee chaired by Prime Minister Clement Attlee decided in secret to proceed with developing a British atomic bomb.³ At about the same time, the Air Staff issued operational requirements for medium jet bombers — the V-bombers — which were to deliver the new weapons.

For one of the Second World War's victorious 'big three', the decision to acquire the most powerful weapon system seemed, then and in retrospect, natural. Britain's economic weakness and its diminished military strength in relation to its two wartime allies made atomic weapons an attractive 'leveller'. With the future of the Anglo-American relationship in some doubt and the emerging Soviet threat increasingly apparent, the bomb offered a way to maintain Britain's status in relation to the United States, and its security against the Soviet Union. While pursuing a national capability, the UK simultaneously sought to restore its atomic relationship with the United States. The latter's commitment to the defence of Western Europe would be the best, and perhaps only, way to secure Britain in the face of the Soviet Union. Thus the pattern for British nuclear-weapons policy for the next 40 years was set.

Britain acquired an operational nuclear capability in 1956 when the first V-bombers armed with the Blue Danube free-fall fission weapon became operational. Even before the UK acquired an operational deterrent, a policy of nuclear deterrence was firmly established as the only possible counter to the threat of nuclear attack.⁴ The 1952 Global Strategy Paper set out the basic stance:

Since no effective defence against atomic attack is in sight, the primary deterrent must be the knowledge on the part of the Kremlin that any aggression on their part will involve immediate retaliation ... with the atomic weapon.⁵

It was also realised that the initial capability would be just that. The atomic breakthrough of 1945 was followed by two further, perhaps more significant, developments. Thermonuclear (fusion) weapons produced several orders of magnitude of greater explosive power and ushered in the nuclear age in a way that modest numbers of relatively low-yield fission weapons perhaps had not. Ballistic missiles offered a way of delivering them that could not (unlike manned bombers) be intercepted. By the late 1950s the Soviets had fusion weapons and ballistic missiles. Britain had neither, and its new deterrent capability began to look obsolescent even as it entered service.

In response to this emerging shorttall in nuclear-weapons capability, in 1953-54 the British government took two related decisions. One was to develop a fusion weapon, or 'H-bomb', and the other to build an intermediate-range ballistic missile (IRBM) called Blue Streak to deliver it. The 1957 Defence White Paper built on earlier thinking, further emphasising the nuclear deterrent at the expense of conventional forces, including an end to conscription.

After several years of diplomatic lobbying, nuclear collaboration with the United States was partially restored in 1954 with Congressional passage of another Atomic Energy Act, which permitted a limited bilateral exchange of information. This was followed in 1956 by a US initiative to station American IRBMs in Britain to help to counter the growing Soviet nuclear capability. Agreement was reached in 1957-58 for the basing of 60 US Thor missiles in the UK, under a 'dual-key' arrangement whereby the consent of both governments was required to authorise their launch. The missiles and their nuclear warheads were supplied by the US, but operated by RAF personnel with an American authentication controller. Highly vulnerable to pre-emptive attack, they did not long remain in service and all were withdrawn by 1963.⁶

Anglo-American cooperation was also intensifying in the field of nuclear targeting, now that the UK had some operational capability. The real breakthrough in cooperation, however, followed the British Grapple series of thermonuclear tests between May 1957 and September 1958.⁷ These coincided with the Soviet launch of the Sputnik satellite and what Washington perceived as a 'missile gap'. These developments gave the US a real incentive for extensive strategic cooperation with its only proven nuclear ally, the UK. The 1958 Agreement for Cooperation on the Uses of Atomic Energy for Mutual Defence Purposes⁸ finally amended the McMahon Act and set the pattern for close and exclusive nuclear cooperation between the two countries that has endured to this day. In particular, the agreement allows the UK to draw on American warhead designs,⁹ though these are always 'anglicised' and the weapons built in Britain. This access to US warhead designs was important because American delivery systems require warheads designed to fit them.

The first British fusion bomb (the one-megaton Yellow San Mk 2) became operational in 1961 and armed an improved series of V-bombers. This capability was still, however, a free-fall bomb delivered by a subsonic manned bomber. It was increasingly vulnerable to pre-emptive attack from Soviet missiles while still on the ground and, once airborne, had to penetrate extensive Soviet air defences. A pessimistic report in June 1961 assessed the UK's deterrent as just 1% effective — an assessment that was not widely circulated.¹⁰ The Blue Steel Mk 1 stand-off powered bomb which entered service two years later only marginally improved the situation as it had a range of only 100 miles, was unreliable and took considerable time to prepare.

As well as an extended range Blue Steel Mk 2 (later cancelled), the solution was to have been Blue Streak. But this was a liquid-fuelled IRBM launched from fixed silos. Though impervious to Soviet defences once launched it was likely to prove as vulnerable to pre-emptive strike as the V-bombers. Accordingly, it was cancelled in April i960. Britain did not have the resources to develop several delivery systems simultaneously and, with the demise of the land-based IRBM, had to turn to the Americans.

There was already some interest in Britain in the US Navy's new submarine-launched ballistic missile (SLBM) Polaris. But the Royal Navy's priorities for the moment lay elsewhere (in aircraft carriers, in particular), while the strategic deterrent was central to the RAF's Cold War role. The American Skybolt air-launched ballistic missile was selected to replace Blue Streak.

From the beginning there were doubts about the wisdom of this reliance on the United States, not least because it was never certain that the Americans would persist with the Skybolt project. Moreover, Skybolt could do no more than improve the performance of the V-bomber force and thereby extend its operational life. It did not solve the problem of what should eventually replace the V-bombers.

Just two years later, in November 1962, the Americans did indeed cancel Skybolt on cost and performance grounds. This caused a minor crisis in Anglo-American relations which demonstrated how reliant the British had become on the US. Polaris was now the only possible option as both manned aircraft and land-based missiles were too vulnerable in a small country relatively close to the Soviet Union. The Skybolt cancellation was followed quickly by a long-planned Anglo-American conference in Nassau in December 1962. The future of the British deterrent now topped the agenda and the Americans were persuaded to support their key ally in maintaining its nuclear capability.

A sea-based deterrent

Almost by default, after all other possibilities had been exhausted, Britain finally got the one nuclear delivery system, Polaris, which met the needs of a small, densely populated island state in straitened economic conditions, even if it did have to be purchased, on favourable terms, from another country.

As a result of the Nassau agreement, the strategic nuclear deterrent was committed to NATO as a contribution to the Alliance's overall deterrent strategy, except 'where Her Majesty's government may decide that supreme national interests are at stake'. As the use of nuclear weapons could only be contemplated under such circumstances this subsequently oft-repeated statement was little more than a diplomatic nicety, though some targeting plans were coordinated through NATO.

Although the missiles themselves were purchased from the United States, their warheads (three per missile) were British designed and built. The submarines were also British, created essentially by inserting a missile compartment in the middle of the existing Valiant-class nuclear-powered attack submarine (SSN) design. Less than six years after the British government committed itself to Polaris, the first submarine, Resolution, was at sea. This was a remarkable achievement.¹¹ In 1969 the Royal Navy took over the strategic deterrent role from the RAF, whose nuclear-capable aircraft were reduced in number and re-assigned to 'theatre' nuclear and conventional roles. The 'deterrent gap'¹² seemed to have been closed.

Polaris did not, however, resolve all Britain's nuclear dilemmas. By now the Soviet Union was known to be developing anti-ballistic missile (ABM) systems. While it seemed unlikely that these could pose a significant challenge to the huge strategic arsenal of the United States, for the UK it was a different matter. The previously anti-Polaris Labour government, led by Harold Wilson, had decided to retain the strategic deterrent, but as a token gesture cancelled a planned fifth submarine in January 1965. With four boats, just a single submarine with 16 missiles could be guaranteed to be on station at all times, though often there were two on patrol. The three warheads of a Polaris missile separated by only about 10 miles after detaching from the missile and could be destroyed by a single exo-atmospheric megaton-range nuclear burst.¹³ One senior MoD official later judged that 'the deployment of the Russian ABM system was not a minor irritant to a country with such a limited deterrent force; it necessitated a major reconsideration of strategic thinking'.¹⁴ Once again, the credibility of the deterrent system was in doubt before it even entered service.

There was a particular difficulty with the Soviet ABM system, as it protected Moscow and an area of several hundred thousand square kilometres around it. For Britain's relatively small deterrent against the Soviet Union to be effective, it had to threaten 'unacceptable damage'. This was the so-called 'Moscow criterion'.¹⁵ Though other targeting options were often considered, it became the consistent view within the British government that only the ability to hit the Soviet capital lent Britain's limited force the required deterrent effect.

The 1972 ABM Treaty, ot which the UK was not a signatory and the amended text of 1974 limited each superpower to just one ABM site with 100 interceptors. This was of critical importance to the UK, as it meant widespread missile defences which could completely negate the small British deterrent would not be deployed. However, it also meant that as the Soviets chose t...

Table of contents

• Cover
• Title
• Copyright
• Contents
• Glossary
• Introduction
• Chapter One A Nuclear Legacy
• Chapter Two A Nuclear Future
• Chapter Three Nuclear Deterrence
• Chapter Four Nuclear Non-Proliferation
• Chapter Five Future Nuclear Capability
• Conclusion
• Notes