What is Nuclear Deterrence?
The strategic concept of deterrence aims to prevent war. It is the justification virtually every nuclear state uses for maintaining nuclear arsenals, including the UK.
The concept of nuclear deterrence follows the rationale of the 'first user' principle: states reserve the right to use nuclear weapons in self-defence against an armed attack threatening their vital security interests.
Possession of nuclear weapons could be seen as the ultimate bargaining tool in international diplomacy, instantly giving any nuclear state a seat at the top table.
The Coalition government has committed to maintaining Trident, the UK's submarine-based nuclear deterrent. The Royal Navy operates 58 nuclear-armed Trident II D5 submarine-launched ballistic missiles and up to 160 nuclear warheads on four Vanguard-class submarines, one of which is always on patrol.
The Foreign Secretary confirmed in May 2010 that the UK would hold in its stockpile a maximum of 225 nuclear warheads; this includes 160 operationally available warheads, plus additional warheads needed to allow for routine processing, maintenance and logistic management.
In March 2012 the Defence Secretary, Philip Hammond, confirmed that HMS Vengeance, one of the Royal Navy's nuclear deterrent submarines, would undergo a £350m upgrade, expected to take three-and-a-half- years. HMS Vengeance is the last of the four ballistic submarines to undergo a complete overhaul and refuel.
Prime Minister Clement Attlee authorised a British nuclear weapons programme in 1947, two years after the USA dropped its first atomic bombs on Japan.
Already in 1945, a general purpose Atomic Energy Research Establishment had been set up at Harwell and in early 1946 a production facility based at Risley was established. In June 1947, Windscale on the Cumbrian coast was named as a safe site for the production of plutonium.
On October 3 1952, the UK conducted its first successful nuclear test, in the Monte Bello Islands off the north-west coast of Australia - and Britain became a nuclear power. The Blue Danube air-delivered bomb entered service in 1953.
A 1958 agreement gave the UK access to American nuclear weapons design information, and in 1962 the US agreed to provide information about its submarine-launched missile system, Polaris. The first Polaris submarine, HMS Resolution, went to sea in 1968. Polaris was later modified in the early 1970s to a uniquely British system known as Chevaline.
In 1980, the Thatcher Government announced plans to purchase the new US Trident missile system, to replace Polaris. The final replacement took place in 1996, and left the UK entirely dependent on the US for its nuclear submarine technology.
Labour announced plans in the 1998 Strategic Defence Review to scale down the UK's nuclear arsenal: to reduce the stockpile of warheads from a maximum of 300 to under 200 (along with 56 missile bodies). The last of the RAF's WE177 nuclear bombs were taken out of service in March that year.
In December 2006, the government proposed that after Trident expired in the 2020s, the number of nuclear warheads should be cut further from 200 to a maximum of 160.
Although the UK's nuclear arsenal guaranteed its continued global influence in the Cold War, it was the nuclear deterrence developed between the USA and the USSR - the belief that any attack would lead to massive nuclear retaliation and 'mutually assured destruction' - that maintained the temperature between the 1950s and 1990s. The Cuban missile crisis of 1962 provided a stark example of both the precariousness and effectiveness of deterrence at the time.
Efforts were made during the 1960s and 1970s to reduce superpower nuclear arsenals and to prevent nuclear proliferation. 187 countries signed up to the 1968 Non-Proliferation Treaty, including the five nuclear powers of the day: the USA, USSR, China, France and the UK. The Treaty aimed to prevent the spread of nuclear weapons technology and to encourage peaceful nuclear co-operation.
However, a number of other states have developed nuclear weapons since the 1968 Non-Proliferation Treaty, including India, Pakistan and Israel.
At a historic summit meeting of the UN Security Council in September 2009, significant steps were taken to reinvigorate the Non-Proliferation Treaty. At the meeting, presided over by President Barack Obama of the United States, 14 heads of state and government unanimously agreed to adopt Resolution 1887 - the UNSC's first comprehensive action on nuclear issues since the mid-1990's.
The Council called on all states to sign up to the NPT and to set "realistic goals" to strengthen, at the 2010 Review Conference, all three of the Treaty's pillars - disarmament of countries currently possessing nuclear weapons, non-proliferation to countries not yet in possession, and the peaceful use of nuclear energy for all.
It also called for all states to refrain from conducting nuclear test explosions and to ratify the Comprehensive Nuclear-Test-Ban Treaty in order to bring it into force as soon as possible. In addition, the Council urged the Conference on Disarmament to quickly negotiate a treaty banning the production of fissile materials for explosive devices.
Following difficult negotiations at the NPT Review Conference in May 2010, all of the states finally agreed on a series of action plans to revitalise the Treaty and increase efforts to prevent the spread of nuclear weapons.
Concern was also expressed at the 2010 Conference about the lack of progress made in the Middle East and it was decided that a conference should be convened in 2012 - to be attended by all States of the Middle East –"on the establishment of a Middle East zone free of nuclear weapons and all other weapons of mass destruction."
Finland is to host the conference, scheduled for the end of 2012, but there have been reports that Israel remains reluctant to attend and suggestions that the conference could now be postponed until 2013.
The threat to humanity as a whole from nuclear weapons has led many to oppose them since their development.
In the UK, the Campaign for Nuclear Disarmament waged a long campaign that was most famously embodied in the Greenham Common Women's Peace Camp, which protested outside the RAF base chosen as a base for US ground-launched missiles from 1981 to 2000. From 1960 to 1989, the Labour Party was committed to unilateral nuclear disarmament.
Nonetheless, deterrence and Mutually Assured Destruction did prevent nuclear war between the USA and USSR, until the collapse of Communism.
Since the end of the Cold War, the nature of the nuclear threat has changed dramatically. The greatest nuclear fear today is that nuclear weapons find their way into the hands of terrorists or 'rogue states', either through autonomous programmes of development or technology passed on, particularly from the former Soviet Union or China.
A policy of deterrence is useless against terrorists, and is less useful against 'rogue states' such as Iran and North Korea, both of which are believed to possess nuclear weapons, because their motivations are not easily understood.
The UK maintains a sub-strategic 'tactical' nuclear capability: 'battlefield' nuclear weapons that are not part of a deterrent strategy. In the past, this role was performed by air-delivered WE177 bombs; today it is performed by Trident.
Although the Strategic Defence Review said the shift from WE177 and Polaris to Trident had reduced the UK's megatonnage of warheads by 70 per cent since the 1970s, Trident is a much more powerful weapon than its predecessors. It has a range of 4,600 miles (compared to 2,500 for Polaris and Chevaline), three times the targeting capability, permitting each missile to hit 48 targets.
When the government was drawing up plans to replace Trident in 2006, anti-nuclear campaigners and many in the Labour party argued Britain should abandon the weapons system altogether. They argued against replacing Trident on moral grounds, saying it would breach the Nuclear Non-Proliferation Treaty and they also questioned the cost - about £1 billion a year between 2012 and 2027. But the government insisted nuclear weapons were a vital part of Britain's defence.
This continues to be the view of the present Coalition government, although it has committed to a "value for money" review of the Trident programme to ensure it is maintained as cost-effectively as possible.
In May 2012, the MOD announced that it would continue to invest £1bn a year over the next five years on facilities at the Atomic Weapons Establishment (AWE) in order to sustain its commitment to the nuclear deterrent.
Later that month the MOD also confirmed that it had awarded contracts worth £350m to UK companies to design the next generation of nuclear deterrent submarines to replace the Vanguard Class submarines. The first Successor submarine is due to be delivered in 2028, and although a final decision on the design will not be made until 2016, the MOD said detailed work had to be undertaken now in order to ensure the new submarines would be "the most technologically advanced, to protect our national security."
However, the Government has also stressed that it will "press for continued progress on multilateral disarmament."
But the protestors remain as vociferous as ever, particularly in Scotland where anti-nuclear campaigners have called on the newly-elected SNP government to fulfil a manifesto pledge to press for the scrapping of nuclear missiles and a halt to their replacement.
The Trident II D5, currently in service, is supplied by the Lockheed Martin Corporation. It is a three stage, solid-fuel missile, 13 metres long, more than two metres in diameter and weighs more than 60 tonnes. Each missile can carry up to 12 nuclear warheads and each Vanguard-class submarine can carry up to 16 missiles.
From 1994 the Royal Navy's Vanguard-class submarines, equipped with the Trident weapons system, succeeded the Polaris missile boats which had maintained a continuous strategic nuclear deterrent for the United Kingdom for almost 30 years.
The current Trident submarines are giant vessels, 150 metres in length and displacing 16,000 tonnes when submerged. In spite of their huge size, they are among the quietest submarines in the world and are extremely difficult to detect.
The submarines' nuclear reactors produce enough power to supply a small town and need to be refueled only after years of operation. The boats produce their own oxygen and fresh water and this enables them to remain at sea almost indefinitely. They can circumnavigate the world underwater if necessary, and patrols lasting several months are routine.
Source: Atomic Weapons Establishment (AWE)
“This Government is committed to maintaining a continuous submarine-based nuclear deterrent. The contracts announced today with BAE Systems, Babcock and Rolls-Royce symbolise an important step towards renewing our nation’s nuclear deterrent into the 2060s."
Defence Secretary Philip Hammond, commenting on the £350m worth of contracts awarded to UK companies to design the next generation of nuclear deterrent submarines – May 2012
"Being a nuclear weapons state comes with the most solemn of responsibilities and that is why we must work together with our allies to make sure the secrets of these weapons stay safe and out of the hands of terrorists."
Armed Forces Minister Nick Harvey – March 2012