On March 23, Deputy Chairman of the Security Council of the Russian Federation Dmitry Medvedev warned that the “nuclear apocalypse” is drawing “closer.” This threat, however oblique, is one of several that Russian officials have made that imply the threat of nuclear use against Ukraine and the NATO states supporting Kyiv. Moscow has spouted this dangerous rhetoric since the start of the Russo-Ukrainian war in early 2022, making threats that are loud, frequent, and extreme.

Some commentators have suggested that Russian nuclear threats are little more than cheap talk. Moscow may hope its threats convince NATO states and Ukraine to accept Russia’s territorial gains; Russia may even intend to use threats to deter NATO states and Ukraine from fighting harder. But threatening to use nuclear weapons doesn’t necessarily mean Russia plans to use them. To this camp of thinkers, that the threats emanating from Moscow have become increasingly commonplace makes them seem even less grave. After all, if bellicose threats are a normal part of politics, doesn’t that suggest they are mere bluffs?

Lauren Sukin
Dr. Lauren Sukin is a nonresident scholar in the Nuclear Policy Program and an assistant professor of international relations at the London School of Economics and Political Science (LSE).
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To answer this critical question, it is important to remember that Russia is not alone in brandishing its nuclear saber—and that there are lessons to be learned from how nuclear threats are used elsewhere. In particular, North Korea, a frequent issuer of nuclear threats, bears key similarities to Russia today. Both countries are isolated, with few allies and an ocean of sanctions through which to wade. In turn, both rely heavily on nuclear weapons. Both North Korea’s Supreme Leader Kim Jong Un and Russia’s President Vladimir Putin are highly personalistic leaders and surrounded by ideological “yes men.” Neither has many checks against their power. Both men are deeply anxious about their legacies and beholden to unlawful and, increasingly, unrealistic foreign policy ambitions. With these similarities in mind, it is precisely because of and not in spite of the fact that Moscow and Pyongyang have repeatedly held their nuclear arsenals over Western heads that leaders should take these threats seriously.

North Korea’s frequent and extreme nuclear threats

On March 24, North Korea’s Korean Central News Agency (KCNA) published an article announcing the testing of a new underwater nuclear attack drone. The article noted this new weapon as part of North Korea’s preparations “for an all-out war and [to] bolster up its nuclear force both in quality and quantity on a priority basis.” It also quoted a statement by Kim referring to “the need to take offensive actions to make the enemy inviting the danger with thoughtless and reckless acts realize the DPRK’s [North Korea’s] unlimited nuclear war deterrence capability being bolstered up at a greater speed.” This type of implicitly threatening language is not unusual coming from Pyongyang. On average, the KCNA publishes forty-nine articles per month containing similarly formulated threats against North Korea’s adversaries.

Similar to Russia, North Korea’s nuclear threats are often dismissed as little more than unreliable “cheap talk.” The most extreme threats sometimes make headlines, but they’re rarely taken seriously as indicators of what North Korea fears or plans. More often, they are simply presented as evidence of an erratic, perhaps even irrational, regime. Many of North Korea’s threats are general or tied to implausible conditions, but even when the regime does make highly specific threats, triggering those conditions then rarely results in the exact threat coming to fruition. Yet, even when such pugnacious rhetoric is a constant, there are lessons to be learned if we examine this behavior more systematically.

My research shows that nuclear threats—even extreme, frequent ones—provide meaning in two essential ways. First, observers can examine patterns in the content of these threats in order to better understand the messenger’s international security concerns. Specifically, states use nuclear threats to draw boundaries around the issues that they care most deeply about. Second, the frequency of threats matters. Even with a noisy baseline, periods with high volumes of threats see their messengers taking accompanying aggressive actions.

The content of nuclear threats, from Pyongyang to Moscow

North Korea most often makes threats about and in response to U.S.–South Korean joint military exercises. More than one-third of North Korea’s threats mention these exercises; this indicates that they are perceived in Pyongyang as major challenges to North Korea’s security. The joint exercises aim to increase interoperability and other military capabilities, but for North Korea they raise fears of a surprise attack, which North Korea then must prepare to counter. (Military exercises have been used as cover for attacks in the past; Russia, for example, amassed troops at the Ukrainian border in 2021 under the guise of military exercises with Belarus.)

A key characteristic of this bluster is that the threats are generally aimed at creating bright lines; although some threats attempt to convince adversaries to fully roll back ongoing programs or significantly alter their approach, states are limited in their ability to achieve much more with this strategy. For example, North Korea cannot compel the United States to roll back already planned or ongoing exercises, but by lambasting these activities, Pyongyang may still believe it has achieved a victory by preventing these exercises from escalating into something worse. This dynamic illustrates the benefits and limitations of threats. North Korea might shout that it will use nuclear weapons if a certain military exercise continues, but the actual, underlying message is that escalation of some kind is likely. Indeed, scholarship has found that North Korea frequently uses provocations such as missile tests to respond if U.S.–South Korean exercises get too close to the border, involve advanced equipment and strategic assets, or employ large numbers of forces. North Korea might not be launching nuclear weapons—as promised—but its threats do seem to reveal real strategic concerns.

How do these lessons translate to the Russian context? Russia’s nuclear threats seemingly reflect a few evolving priority objectives in the Russo-Ukrainian war. These include deterring NATO from implementing a “no-fly zone” over Ukraine and preventing NATO and Ukraine from driving Russian forces out of disputed territory. These threats—where there has been repeated Russian rhetoric—constitute fairly bright lines. The threats do not compel a reversal of any existing policies but are designed primarily to prevent new actions that would be intolerable for Russia. And, for better or for worse, those threats have largely been effective—perhaps because the West understands that they are credible signals, if not necessarily of some immediate Russian intent to use nuclear weapons, at least of Russian willingness to escalate if the bright lines it sets are crossed.

But there are limits to what Russia can achieve with nuclear threats. Russia has tried, albeit sparingly, to use nuclear threats to affect geopolitics outside of the immediate concerns of the Russo-Ukrainian war. For example, Moscow initially threatened nuclear consequences if NATO expanded—yet was unusually silent after Finland’s recent accession. Russia has also brandished its nuclear saber in the occasional attempt to reverse ongoing Western aid to Ukraine. In January, for example, Vyacheslav Volodin, the chairman of Russia’s State Duma, threatened that continued Western military support to Kyiv would end in “global catastrophe.” But reversing this ongoing, major multilateral policy is beyond the scope of what even the most daring nuclear rhetoric could plausibly achieve.

Not just crying wolf

A second way that nuclear threats can reveal strategic meaning is through their frequency. Scholars have long argued that, when it comes to states, actions speak louder than words. After all, it is easy for a leader to make verbal threats; it is harder and far more consequential to follow through on them. Thus, when leaders lie, they lose credibility, and their words carry less meaning. From this point of view, North Korea would certainly have a credibility problem. Between 1996 and 2018, Pyongyang conducted one military provocation—such as a cross-border shooting or a missile test—for every seventy-eight threatening articles published by the KCNA. As a result, some scholars and analysts have suggested that North Korea’s threats should not be taken seriously.

My research, however, argues that this perspective gets it wrong. Instead of simply “crying wolf,” there is strong evidence that states make threats when they actually feel threatened, and the more threatened they feel, the more likely it is they will act on those threats. Of course, it may be easier to threaten one’s enemies than to send soldiers to back up those threats, but both behaviors are primarily triggered by moments of insecurity that are worth understanding.

There is ample evidence to support the contention that when North Korea’s threats get much louder, Pyongyang is ready to take risks. After all, North Korea may make regular threats—by 2017, more than 16 percent of all English-language KCNA articles contained threats—but to go from frequent to a flood is not so simple. It’s not trivial for the KCNA to produce English-language articles; the process is selective and highly centralized. And although it’s unlikely, any threat can unintentionally spiral, whether by convincing an adversary to build up their capabilities or by triggering outright aggression. Thus, when states are most willing to endure the risk that their threats may inadvertently escalate, they should issue said threats more frequently. Indeed, because states make more threats when they feel more threatened, identifying changes in the volume of threats can help determine when escalatory, aggressive military actions might be taken.

This approach holds true for North Korea. In my research, I analyze more than 124,000 KCNA articles to systematically characterize Pyongyang’s threats against its adversaries. Surges in the volume of threats are often precursors to North Korean military actions, as the graph below shows. This illustrates how threats often reflect an underlying state of heightened agitation and resolve in Pyongyang.

So, although a singular North Korean threat to “beat [the United States] to a jelly” might not mean that any escalation will quickly occur, a week that is jam-packed with threats should be a serious warning. As the graph below shows, North Korea ramps up its threat production prior to provocations, and it then quiets down in the event’s aftermath. For example, in the ten days prior to a missile or nuclear test, North Korea issues an average of three threats per day—almost twice as often as it does two months before a test. Understanding this pattern is pertinent. It provides a way for analysts to understand the state of Pyongyang’s threat perception—and perhaps even forecast potential provocations.

Further, threats don’t just precede provocations, they seem to predict them (see figure 2). North Korea watchers have several methods—such as studying satellite imagery or seasonal patterns—to identify when the country may be gearing up for a new test, but for the most part, these approaches offer only an approximate sense of Pyongyang’s timeframe. For example, scholars have been expecting a seventh North Korean nuclear test for months.

Analyzing the frequency and content of threats, however, could provide a way to identify specific times during which provocations might happen. As the graph above shows, months with twenty-five or fewer threats have less than a 40 percent chance of a provocative action, while the odds in months with seventy-five or more threats are between 60 and 80 percent. This approach can predict action on small timescales as well. A week with nine more threatening articles than usual is associated with an eleven percentage-point increase in the probability that North Korea will test a missile or nuclear weapon in the following week. 

This approach could have important added value in more precisely predicting the timing of provocations. As North Korea’s threatening messaging has gotten louder, the frequency of its missile tests has skyrocketed while the regime potentially gears up for a seventh nuclear test.

If the lessons from Pyongyang can travel to Moscow, the unfortunate conclusion may be that Russia’s nuclear threats should be a source of major worry. The numerous nuclear threats emanating from Russia over the past year may suggest that not only does the regime see its current position as deeply precarious but also that the regime is willing to take severe risks to improve its security.

While Russia’s nuclear threats may not necessarily mean that the country is gearing up for actual nuclear use, at least not in the short term, it’s unlikely to be off the table, either. More frequent nuclear threats could indicate that Moscow is squirming, and that escalation, in turn, might be coming. That could occur in the form of further risky nuclear policies—such as speeding up the process of deploying nuclear weapons in Belarus, producing additional dual-capable delivery systems, or even expanding the Russian nuclear arsenal—or it could mean additional offensives in Ukraine, up to and including limited nuclear use. Such actions would represent the urgency of Russia’s challenge to the global nuclear order and reveal a deep-seated discomfort among Putin and his inner circle.

To ignore or dismiss Russia’s threats as crying wolf would be perilous and naïve. The repetition of Russian nuclear threats makes the situation more—and not less—concerning. This rhetoric is not merely strategic manipulation of Western sentiments but instead revealing of the sort of high anxieties in Moscow that could lead to risky decisionmaking, whether nuclear in nature or not.

Curbing nuclear threats

Unfortunately, the international community has very little power to prevent the use of nuclear threats. Although the Treaty on the Prohibition of Nuclear Weapons (TPNW) does formally ban nuclear threat making, neither Russia nor any other nuclear country has joined the agreement. There are otherwise no explicit laws and very few norms that could be leveraged to restrain Russia, North Korea, or even the United States from bombastic nuclear threat making.

Some might argue that the best response, in that case, is to double down on the actions that provoked Russia’s nuclear threats, thereby showing leaders of nuclear states—and states that may want nuclear weapons—that this strategy does not achieve the desired results. My research, however, implies otherwise. Nuclear bombast often precedes provocative actions—but that chain reaction can be stopped if the threat that the messenger faces recedes. On the other hand, if the threatening rhetoric is ignored or even flouted, insecurity will stew until it bubbles over in some act of aggression. Consider, for example, North Korea’s threats calling for U.S.–South Korean military exercises to cease. Scaling up these exercises to show North Korea that its bullying will have consequences might sound like a satisfying strategy, but it is one that will most likely further ratchet up tensions by encouraging a reciprocal act of hostility. Quietly continuing the exercises as planned—or even slightly scaling them down—could avoid this trap. Unfortunately, managing a tense threat environment is a delicate balancing act. Cancelling exercises altogether would hardly be a solution, either, lest it embolden North Korea (while sparking other problems for the U.S.-South Korean alliance).

If nuclear threats are not simply “cheap talk” but, instead, convey real meaning about a messenger’s concerns and willingness to take risks, then forcefully resisting those threats is a strategy that deserves careful consideration in light of the potentially catastrophic costs. When Russian officials issue a new nuclear threat, it is important to assess the threat’s plausibility. My research suggests threats are most credible when repeated and when they are linked to specific conditions (such as on-the-ground behaviors in the Russo-Ukrainian war). Conversely, one-off threats or threats about linked issues (such as NATO membership or broader policies) should be less critical. 

Even caught between a rock and a hard place, the international community can still take action to make it clear that threatening nuclear rhetoric should stay just that: rhetoric. Moscow ought to be certain that any use of nuclear weapons will not, in any way, be tolerated. If such a tragedy happens, it must be met with immediate, resounding, global condemnation, as well as a laundry list of accompanying punishments, from even more sanctions to Russian exclusion from international regimes. Here, too, there are lessons to be drawn from North Korea. Moscow ought to know, without a doubt, that nuclear use would make it a pariah state, adding one more item to the list of its similarities with Pyongyang. After all, it is in the interest of all that Russia remember its vital pledge: that “nuclear war cannot be won and must never be fought.”

This article is a product of a workshop on “The Future of Nuclear Weapons, Statecraft, and Deterrence after Ukraine” hosted by the University of Pennsylvania’s Perry World House on April 4, 2023.