Nuclear weapons technology continues to develop and evolve. This House of Lords Library In Focus examines whether those developments in our multi-polar world, particularly in the field of tactical nuclear weapons, are increasing the risk of a nuclear conflict.

New weapon capabilities

Has the world moved a significant step closer to nuclear conflict?

That is the question commentators and policy-makers are asking following the move by the United States to deploy ‘tactical’ nuclear weapons for the first time. The United States is installing its first low-yield Trident warhead on a submarine patrolling the Atlantic Ocean.

The new W76-2 warhead has an explosive yield of five kilotons. This is a third of the power of the bomb dropped on Hiroshima and considerably lower than the 90 and 455 kiloton warheads on other US submarine-launched ballistic missiles.

The Pentagon has also briefed reporters on a military exercise which simulated a ‘limited’ nuclear exchange with Russia. This was controversial given its implication that military planners may be working to an assumption it is possible to fight, and win, a battle with nuclear weapons without it leading to an all-out and potentially world-ending conflict.

US Nuclear Posture Review

The United States commissioned the new weapon following the 2018 Nuclear Posture Review, requested by President Donald Trump. This  determined such capability was needed to deter Russia’s use of similar weapons.

Advocates of low-yield weapons argued that the United States had no effective deterrent against Russian capability. This is because the size of its existing weapons and their formidable destructive potential would prevent their usage in conventional warfare, for fear of an escalation into a global nuclear war.

Russia’s arsenal

Both Russia and the United States have long had tactical nuclear weapon capability. This was reduced on both sides following the period of disarmament that followed the Cold War.

However, this process went further and deeper in the United States. Though it also undertook a significant reduction, Russia held onto more tactical weapons. Reportedly this was to offset the effect of more advanced and efficient US conventional forces and to a lesser extent Chinese conventional forces.

Russia does not release figures on its current capabilities. The 2018 National Posture Review estimated the Russian arsenal to be around 2,000 non-strategic nuclear weapons. Russia is also in the middle of a process of modernising and updating its nuclear capabilities. This includes the developments of new weapons such as the delivery system known as the Burevestnik nuclear-propelled cruise missile.

The development of Russian capability has led to pointed exchanges between Russian and NATO officials over security in Eastern Europe. In particular, the NATO Secretary-General, Jens Stoltenberg, has demanded Russia dismantle its short-range missile system, saying the alliance may be “forced to respond”.

Other countries’ capabilities

Yet, in the current multipolar world, there are several other countries capable of deploying what could be described as tactical nuclear weapons. 

Of these nations, Pakistan is unique in being the only one to explicitly state it embarked upon a plan to develop tactical nuclear capability.

However, several other countries also possess weapons that, if they were part of the Russian or American arsenals, could be described as tactical.

This includes China. The Chinese state does not officially have tactical nuclear weapons, given its nuclear and regional missile capability., However, Pentagon military planners are reportedly actively planning as if China would be able to bring tactical weapons to bear.

Of the other nuclear powers, France describes all its nuclear weapons as strategic. This includes even the short-range ASMPA air-launched cruise missile. Similarly, India has several weapons systems that could be described as tactical, but classes all its capabilities as strategic. The same could be said for the Israeli and North Korean arsenals.

The United Kingdom has no nuclear weapons it classes as tactical. In evidence to the House of Lords International Relations Committee in 2019, Rear Admiral John Gower, former Assistant Chief of Defence Staff, said the UK dispensed with the last such capability in 1994.

A greater risk?

The International Relations Committee warned in 2019 that the risk of the use of nuclear weapons had increased. This was in the context of rising inter-state competition, a more multipolar world, and the development of new capabilities and technologies.

The committee argued that the programmes of some nuclear possessor states go “well beyond” what can properly be described as modernisation. The committee highlighted developments of new technologies including in the field of so-called tactical nuclear weapons, which could potentially increase nuclear risk.

Chair of the committee Lord Howell of Guildford concluded the chance of nuclear conflict was greater now than at any point in recent decades. He said:

Disintegrating relationships between nuclear possessor states, new capabilities and technologies, mixed with a lack of communication and understanding, mean that the risk of nuclear weapons being used is greater now than it has been since the Cold War.

In response, the Government described the security environment as increasingly uncertain. It added ministers continue to work with the UK’s allies to encourage all nuclear states to recognise their responsibilities and work towards gradual multilateral disarmament within the framework of the Non-Proliferation Treaty (NPT).

What next?

The NPT will undergo the latest in a cycle of five-yearly reviews in New York between 27 April and 22 May 2020—an event which will also mark the 50th anniversary of the treaty entering into force in 1970.

The summit will gather representatives from the traditional ‘P5’ nuclear states of the United States, France, China, Russia and the United Kingdom, the newer nuclear-capable states such as India and Pakistan, and the large contingent of Non-Nuclear Weapon States (NNWS), each with their own agendas to pursue.

It remains to be seen how developments since the last conference, and arguable weakening of the non-proliferation regime inherent to the development of new missile technologies and capabilities, will be addressed if the NPT is to survive well into the future.

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