Late last month, Vladimir Putin made headlines — as he has been wont to do, especially since February 2022 — with a new statement on Russia’s willingness to use nuclear weapons. The specific line that raised eyebrows was his declaration “that aggression against Russia by any non-nuclear state, but with the participation or support of a nuclear state, be considered as their joint attack on the Russian Federation”. Kremlin spokesman Dmitry Peskov also stated that adjustments are being correspondingly formulated for Russia’s nuclear deterrent doctrinal document. The clear implication was that NATO states enabling Ukrainian conventional strikes on Russia against targets that Moscow considers vital to its security would face the full range of Russian retaliatory options, which includes the world’s largest nuclear arsenal. 

The motive behind such an explicit elaboration of Russian declaratory posture is not hard to discern. One of NATO’s three nuclear powers — the UK — has recently been pushing the biggest and best-armed of the other two for permission to approve Ukrainian strikes into Russia using UK-supplied long-range conventional weapons (specifically the Storm Shadow cruise missile). Moscow will fear that if such permission is granted — and especially if Kyiv receives approval to employ US weapons in a similar capacity — targets central to the Putin regime’s hold on power, such as key military headquarters and even political/prestige targets around the capital itself, could be at risk of conventional destruction. This explains last week’s effort to doctrinally link both the attacking and the enabling state: Moscow hopes to make the NATO states supplying and potentially approving the using of such conventional weaponry sufficiently fearful of the retaliatory consequences of striking targets perceivably vital to the Russian regime’s survival that they refrain from permitting and facilitating such attacks. 

Cheap talk? 

All of this begs the question, however: do such statements actually matter? More specifically, does declaratory nuclear posture — what states say about the circumstances in which they would resort to the absolute weapon — convey meaningful information about their future behaviour, or is it just “cheap talk”? After all, states have been rattling nuclear sabres ever since such weapons’ employment against Japan in 1945 — including Russia itself, loudly and often, before and since its botched invasion of Ukraine — yet without ever being imprudent enough (thus far) to cross the post-Nagasaki threshold of using them in anger. 

The purpose of such a declaratory escalation is to “amplify uncertainty” over whether nuclear weapons may ultimately be used

The short answer — predictably — is “a bit of both”. To an extent, all declaratory doctrine is just “cheap talk”…and in this instance, Russia making such a declaration neither increases Russian capabilities nor (crucially) lessens NATO’s capability to inflict unbearable retaliatory pain. It remains just as true that — if Moscow responded to a NATO-backed conventional strike on Russia by escalating to nuclear use — NATO could do the same right back to Russia. And for all its bravado, and despite having got itself deep in the mire in Ukraine, the Putin regime’s desire to see itself destroyed in an atomic firestorm presumably remains low. 

However, it is also true in this case that the Kremlin is attempting to build a specific link to address a novel possibility: that targets vital to Russian regime survival — or at least cast as such by Moscow — might be destroyed using conventional weapons in the hands of a non-nuclear power armed by a nuclear power. In a basic sense, it is obviously correct that — if the UK, France, or the US supplied such weapons that were then employed by Ukraine in such a way — such an attack would have been enabled by a NATO nuclear power. Beyond that baseline understanding, Moscow may infer — rightly or wrongly — that Ukraine could not employ Storm Shadow (or other similarly advanced NATO munitions) against Russia without the supplier state being ‘in the loop’ in terms of targeting and command/control of the weapon. Hence the explicit declaration that Russia would treat such a strike as making the UK/US/France/whoever an actual combatant party to the war (as opposed to the suppliers merely being Ukraine’s arms depot). 

Of course, the possibility that Russia might use nuclear weapons in response to a conventional attack — especially a big one that threatened national survival (which the Kremlin probably equates with regime survival) — has always been there in the background, as it is for any nuclear power. Indeed, NATO never ruled-out nuclear first use during the Cold War, precisely because it thought it might need to resort to nuclear weapons to deter/defeat an overwhelming Soviet conventional attack. But stating it explicitly increases the political commitment, in the eyes of both domestic and external audiences, thus tying — or at least somewhat entangling — decision-makers’ hands. Those audiences include not only ordinary citizens, but also (for example) the elites on which a regime’s authority might rest and the subordinate commanders tasked with implementing a state’s military posture. This is thus a key way in which talk is not just “cheap” (political science literature theorises such effects as ‘audience costs’). 

A competition in risk-taking

The Kremlin’s hope will thus be to increase their deterrent effect, by increasing the perceived likelihood of nuclear retaliation. After all, between actors with secure second-strike nuclear arsenals like Russia and NATO, the balance of resolve — each side’s perceived willingness to escalate to actions that they both know would ultimately be catastrophic — matters more for successful brinksmanship than the balance of power (since both sides have equal capacity to inflict limitless destruction). And their hope does have a rationale behind it: by making a (costly) political commitment to such retaliation in the eyes of domestic and international audiences, they do increase the perceived likelihood of nuclear retaliation by at least some amount. As Shashank Joshi — The Economist’s well–qualified Defence Editor — rightly observed immediately after Putin’s statements, the purpose of such a declaratory escalation is to “amplify uncertainty” over whether nuclear weapons may ultimately be used (thereby increasing NATO’s fear and thus strengthening Russian deterrence). But as prior scholars have observed, for there to be uncertainty about whether another state might undertake some hostile action — along with all of the caution that such uncertainty might breed in our own policy — there has to be at least some possibility that they would indeed do so. It is that possibility that audience costs can amplify, especially given the interaction with decision-making psychology under the pressure of commitment. 

Obviously, different people will have different opinions on whether this is a negligible effect — because they think Russia’s nuclear bluster is still all bluff — or whether it is actually more substantial, because of the way in which such a public (and thus costly) political commitment then motivates and constrains behaviour, and given a risk that initially lower-level retaliatory actions could lead up a tit-for-tat ladder towards atomic catastrophe. Different people will also have different appetites to bear whatever escalation risk there is, based on the relative importance of the interests that they judge are at stake. But one thing we can say is that decision-makers in Paris, London, and especially Washington will listen very carefully to the meaning of — and potential commitment embedded within — any Kremlin statement that appears to make nuclear use even a fraction more likely.