Dr Rod Thornton, Defence Studies Department, King’s College London and Dr Marina Miron, Associate Fellow, Defence Studies Department, King’s College London

Once confined to bad memories of the Cold War, it seems that with the conflict in Ukraine the spectre of nuclear war is back on the geopolitical agenda. 

The rhetoric now being used in Russian political and media circles about the possible use of nuclear weapons, not only in Ukraine itself but also further afield, is as stark as it is threatening. President Vladimir Putin has voiced his own view in no uncertain terms. He has recently expressed concern at the ‘interference’ regarding Ukraine by NATO states – and the ‘Anglo-Saxons’ in particular. If this, as he puts it, ‘creates strategic threats for Russia’ then Russia will engage in a ‘lightning strike’ in ‘retaliation’. Such a ‘lightning strike’ is taken by Russian observers to refer to the use of nuclear weapons. And the United Kingdom seems to be a favoured target according to various Russian nationalist pundits on mainstream TV in Russia. 

There is talk of the ‘nuclear annihilation of Great Britain’. One commentator put it thus – and referring to a new Russian strategic missile (ICBM) – ‘One Sarmat will be enough to solve the problem of Foggy Albion once and for all.’ The UK, obviously, being the ‘Foggy Albion’ in question. In the same vein, another analyst stated that, ‘One Sarmat and that’s it ­­– there are no British Isles.’ Yet another talked of using a nuclear-armed Poseidon drone (a kind of large torpedo) that would explode underwater near the UK’s shores and create a tidal wave that would ‘plunge Britain into the depths of the sea’. 

Moreover, Margarita Simonyan, the head of Russia Today, the main state media organisation in Russia, seems to think nuclear war is very much an option: ‘Either we lose in Ukraine, or the Third World War begins. Personally, I think the path of the Third World War is more realistic.’ Depressing for both the West and, indeed, for Russia. But that’s okay, according to Simonyan because in any large-scale nuclear conflagration that would characterise such a war, the Russian people will be just fine while those in the West won’t: ‘Well, we’re going to heaven, and they’ll just die.’ – she was quoting from what Putin himself had said in 2018 when he used this exact same phrase.  

All this is worrying. But maybe there are saner voices in the Russian political firmament? Maybe the urbane Russian Foreign Minister Sergei Lavrov has been less provocative? Even he, though, has warned that there is a ‘very, very significant’ risk of a nuclear war breaking out over the Ukraine crisis. He went on, ‘The danger is serious. It is real. It cannot be underestimated.’ Of course, such comments, as with those of Putin, could be looked upon as merely strategic messaging – a warning to NATO countries to limit their assistance to Kyiv. As such, this may all be seen as just sabre-rattling and thus not to be taken too seriously. But should we take them seriously?

When it comes to the likelihood of Moscow’s use of nuclear weapons, we must understand four particular factors that could influence any decision-making. Overall, these factors indicate that the Kremlin can generally be seen, when compared to NATO countries, to have a lower threshold for the use of such weapons. 

The first factor relates to the strategic level. Moscow, since the end of the Cold War, has always looked upon its conventional military forces as far weaker than those of NATO. This means that, and in terms of deterring any future attack on its territory by NATO (taken seriously in the Kremlin), it has come to lean heavily on its nuclear deterrent capability. Hence, over the last three decades, Russia has been careful not only to maintain but also to continually modernise its nuclear triad (i.e., weapons delivered by platforms based on land, sea or in the air). There are often exercises to test the readiness of the country’s nuclear triad. The last one was only in February, just a few days before the current war began.  Given that there is this leaning on its nuclear potential, there has always been a sense that Moscow would employ its nuclear arsenal at a lower point in any crisis/conflict situation vis-à-vis NATO than the Alliance itself might contemplate. Moreover, and in light of this standpoint, Russia – unlike countries in the West – has also continued to maintain a significant domestic national resilience capacity in the event of a full-scale nuclear war (bomb shelters, civil defence arrangements, medical facilities, etc). The Russian state and people are far more prepared for a nuclear exchange than is any western country. 

The second factor influencing the possible use by Russia of nuclear weapons is perhaps more pertinent in the current situation. This involves their use at the non-strategic or tactical level. Any long-term reading of articles in Russian military journals certainly gives the impression that the employment of nuclear munitions on a battlefield (launched from missiles or artillery shells) is understood differently than in western militaries. For the Russians, nuclear weapons seem to be treated merely as munitions with just more of an explosive effect – one up from thermobaric. There appear to be few cultural barriers, institutional or ethical constraints evident when the Russian military discusses the use of nuclear weapons on a battlefield. The Russian military, indeed, in recent large-scale exercises prior to the current war has brought into play its tactical nuclear capabilities.

The third factor – and one that is often missed by those reviewing the activities of the Russian military – is the emphasis given by it to the role of producing psychological effect on any enemy during any operation. The form this ‘psychological warfare’ takes could be manifest in the use, at one end of the spectrum, of basic information warfare techniques (media messaging, etc.) all the way up to the imposition of massive kinetic destruction to create mass psychological effect on opponents. In term of the latter, we see in the current war the Russian military trying to destroy complete cities in Ukraine through artillery fire and bombing. If you destroy the city, runs the logic, you will likewise destroy the morale of their defenders and surrender will result. Here is the temptation to use tactical nuclear weapons: the destructive effect they can produce against a Ukrainian city (perhaps one not so far damaged appreciably) could be seen to have a distinct role as part of this logic. Indeed, some Russian commentators see that the Russian military should employ what is ‘its main advantage [in Ukraine] – tactical nuclear weapons.’

The fourth factor that might influence any Russian decision to use any tactical/battlefield nuclear weapons comes with what is taken to be the Russian strategic notion of ‘escalate to de-escalate’. This involves the idea that if things are going badly for the Russian military in Ukraine (or in any future campaign) then it could bring any offensives against it to a halt by employing a nuclear weapon – again, probably against a Ukrainian city. The hoped-for result would be that this ‘escalation’ to nuclear weapons would shock Ukrainian forces into calling for a ceasefire. This would then ‘de-escalate’ the whole war in Moscow’s favour. While this Russian idea of ‘escalate to de-escalate’ has come in for some questioning, its influence cannot easily be dismissed.

As noted, all of this is alarming. But it is not unthinkable. Western analysts with no axe to grind concur that there is a distinct danger here. As Scott Sagan, a senior fellow at Stanford’s Spogli Institute for International Studies puts it, ‘Putin could order the Russian military to drop a single nuclear bomb on a Ukrainian city to try to coerce the Zelensky government into immediately surrendering. This frightening scenario is not fanciful. It is, after all, effectively what the United States did to Japan in 1945.’  

But however alarmist this all might sound, there should, though, be some warning of any recourse by Moscow to its nuclear arsenal. Their use would not be occur on the whim of some local commander. A good deal of debate and preparation would have to precede any use of even a tactical nuclear weapon. This means that there would a significant degree of signals ‘chatter’ across communications means within the Russian body politic and the military itself. Western signals intelligence (SIGINT) organisations would pick up on this ‘chatter’. Moreover, NATO satellites would also notice any activity pointing to the preparation of nuclear munitions at certain bases and in the field. If the communications traffic is, indeed, picked up and if there are visible signs of preparation for nuclear use then western and UN diplomatic/deterrence measures would need to move into overdrive to make Moscow see the benefits of restraint. They may succeed. 

All this having been said, and however dangerous the situation might appear, there will still be wise counsels in Moscow who should be able to provide prevailing influence when it comes to any decision-making in regard to ‘going nuclear’. We should rely on rational actors; they will still exist in Russia.