With Russia’s ongoing war in Ukraine, now is a good time to take note of a little-spoken-of, but glaring, imbalance between America’s and Russia’s nuclear arsenals—and how it could affect stability in Europe and the interests of the United States and those of its European allies and partners.

If asked, many Americans and Europeans probably believe that the United States and Russia are pretty evenly matched in terms of the number of nuclear weapons both sides have in their arsenals. While their beliefs are entirely understandable, they are not completely correct.

Under the 2010 bilateral New Strategic Arms Reduction Treaty—also known as New START—the United States and Russia have a similar number of deployed strategic (i.e., high-yield and long-range) nuclear weapons: 1,550 deployed nuclear warheads each. But not all of Washington’s or Moscow’s nuclear weapons are covered by New START.

Indeed, Russia has nearly a 10:1 advantage over the United States and NATO in non-strategic (i.e., low-yield and short-range) nuclear weapons (NSNWs).

Assessments based on open sources estimate that Russia has about 2,000 NSNWs. It is similarly assessed that the United States and NATO have about 200 NSNWs in their arsenal. It is postulated that half of those U.S.-NATO weapons are located in the United States and half are based in Europe as part of NATO’s nuclear forces.

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While capable of significant destruction, these tactical nuclear weapons are lower in yield—or explosive power—and are meant for use on the battlefield against military installations or troop and equipment concentrations as opposed for use against counterforce or countervalue targets such as ICBM missile fields, command and control nodes, and or population centers (e.g., cities).

It is believed that Russia can deploy these weapons on multiple tactical systems including dual-capable short-range or theater ballistic missiles, torpedoes, and anti-ship missiles. Indeed, it is expected that Russia’s new hypersonic weapons may be dual-capable (i.e., conventional or nuclear armed) as well.

Major nuclear weapons states, including Russia, have said that a nuclear war could never be won and therefore should never be fought. However, there are deep concerns among policy makers and security analysts outside Russia about whether Moscow fully embraces that idea or if it is just convenient diplomatic rhetoric.  

Also of increasing concern is a Russian military doctrine associated with battlefield nuclear weapons known as “escalate to deescalate.” This topic is of particularly interest right now with the war in Ukraine ongoing since late February 2022. According to the 2018 U.S. Nuclear Posture Review (NPR):

“Russia considers the United States and the North Atlantic Treaty Organization (NATO) to be the principal threats to its contemporary geopolitical ambitions. Russian strategy and doctrine emphasize the potential coercive and military uses of nuclear weapons. It mistakenly assesses that the threat of nuclear escalation or actual first use of nuclear weapons would serve to “de-escalate” a conflict on terms favorable to Russia. These mistaken perceptions increase the prospect for dangerous miscalculation and escalation.”

The NPR further asserts that:

“Moscow threatens and exercises limited nuclear first use, suggesting a mistaken expectation that coercive nuclear threats or limited first use could paralyze the United States and NATO and thereby end a conflict on terms favorable to Russia. Some in the United States refer to this as Russia’s “escalate to de-escalate” doctrine. “Deescalation” in this sense follows from Moscow’s mistaken assumption of Western capitulation on terms favorable to Moscow.”

Though the Russians seemingly refute the existence of this doctrine by its American name at least, some sources assert that the policy may actually have been developed in the late 1990s, when now-Russian President Vladimir Putin was chairman of the Russian National Security Council under President Boris Yeltsin.

The idea behind escalate to deescalate is that Russia might employ one tactical nuclear weapon (or more) during a conventional conflict with NATO forces for the purposes of preventing a defeat, consolidating territorial gains, or even freezing a conflict in place without the prospect of further fighting.

Indeed, because of the large, nearly 10:1 disparity between the number of Russian and U.S. tactical nuclear weapons, Moscow may think a nuclear response from NATO is not a credible threat due to Russia’s asymmetric advantage. Other factors may also play a role in Russian calculations, including a perception that NATO’s large membership would have difficulty finding a political-military consensus on an appropriate response, including a nuclear option.

An example of the potential use of this Russian nuclear doctrine in a hypothetical scenario might be helpful here:

Moscow attacks one—or all—of the Baltic States with its conventional forces to establish control over some, or all, of these nations’ territory, returning them to Russia’s control as they were in the Soviet era. Invoking Article V, NATO responds with conventional forces to protect and restore the sovereignty of these three allied states.

Concerned about the inferiority of its conventional forces in this fight against the allied powers, Moscow then contemplates exploding a low-yield tactical nuclear weapon somewhere in theater as a warning of Russia’s potential escalation from the conventional to the nuclear domain of warfare, including the potential future use of high-yield, strategic nuclear weapons.

In Moscow’s eyes, perhaps NATO will become concerned about the possible escalation of the fighting from the conventional to the nuclear—especially Russia’s potential use of more powerful nuclear weapons against European and American cities. In response, NATO may consider pausing its counteroffensive against Russian forces in the Baltics.

Indeed, Moscow may misperceive that if NATO does not have sufficient tactical nuclear weapon capabilities to  respond in kind, it would be inclined to seek de-escalation rather than launch a strategic nuclear weapon at Russia and risk moving further up the escalation ladder—a response that could lead to all-out nuclear war.

Using its tactical nuclear weapon advantage over NATO and having strategic nuclear parity with Washington, Moscow could threaten additional low-yield nuclear strikes unless fighting ends on Russia’s terms. Ideally for Moscow, NATO might decide that there is no good option available to respond and chooses to cease hostilities, locking in Moscow’s ill-gotten gains in the Baltics.

With these political-military calculations in mind, Russia takes a chance on the expected NATO response and explodes a 10-kiloton tactical nuclear weapon near or in the European theater. As a result, nuclear deterrence fails for the first time in history not due to the use of strategic nuclear weapons that so many people are aware of, but the imbalance of battlefield nuclear weapons between NATO and Russia.

While the preceding example addresses a potential attack on NATO, these NSNWs also could play a role in the ongoing war on Ukraine.

Russian forces continue to face incredible resistance from the Ukrainian government, military, and people. Military and other aid from NATO nations and others continue to pour into Ukraine. The Russian military is struggling and taking far greater losses than they likely anticipated. Observers are increasingly concerned that the Kremlin may escalate the war with the use of weapons of mass destruction, including tactical nuclear weapons.

Moscow could certainly decide to move the war in Ukraine from the conventional level to the nuclear level at any time. But under what circumstances might Russia use a tactical nuclear weapon directly against Ukraine—or as part of the conflict—in an effort to determine the outcome of the war in Moscow’s favor?

In late March 2022, shortly after Russia’s latest invasion of Ukraine, Dmitry Medvedev, former Russian president and current deputy chairman of the Russian Security Council, outlined Moscow’s policy on using nuclear weapons. According to a press account, Medvedev said:

“We have a special document on nuclear deterrence. This document clearly indicates the grounds on which the Russian Federation is entitled to use nuclear weapons. There are a few of them, let me remind them to you: number one is the situation, when Russia is struck by a nuclear missile. The second case is any use of other nuclear weapons against Russia or its allies. The third is an attack on a critical infrastructure that will have paralyzed our nuclear deterrent forces. And the fourth case is when an act of aggression is committed against Russia and its allies, which jeopardized the existence of the country itself, even without the use of nuclear weapons, that is, with the use of conventional weapons.”

Medvedev’s explanation on Russian nuclear doctrine is relatively clear, but he failed to note the escalate-to-deescalate doctrine. And that doctrine arguably is what creates the most likely scenario in which Moscow resorts to the use of nuclear weapons in the near future.

The war in Ukraine has not gone well for Russian President Vladimir Putin. What the Kremlin thought would be a fast assault on the capital, Kyiv, followed by the fall of the Ukrainian government, has turned into a difficult situation, which has seen Russian forces losing general officers, troops, and equipment at an alarming rate.

The outcome—once thought to overwhelmingly favor Moscow—remains inconclusive. 

This state of affairs does not bode well for the Kremlin. Even authoritarian leaders such as Putin care about public opinion at home and the effect it might have on the regime’s control over the country. Russia needs to achieve some sort of “victory” to justify its military adventurism in Ukraine, especially among the Russian elite and national security establishment.

Losing the war in Ukraine would have repercussions on Russia internationally, too, including significant reputational costs, strained diplomatic relations and likely pariah status in international organizations,  economic  costs based on a variety of punitive sanctions, and a demoralized, depleted Russian military that may not be able to effectively project power abroad.

In other words, losing the war in Ukraine has the potential to be painful for Putin, Russia, and the Russian people – and this is when, unfortunately, the use of nuclear weapons potentially comes into play for Moscow.

Indeed, Putin might decide to use a NSNW (or more than one) in this yet unproven escalate-to-deescalate plan to advance Russia’s unjust goals of politically subjugating the Ukrainian government and the Ukrainian people and disarming the Ukrainian military.

There is robust debate about the efficiency and effectiveness of using a NSNW on the Ukrainian battlefield to advance Russian goals. There are, however, other options. For example, Russia could explode a low-yield, tactical nuclear weapon for political effect over an unpopulated area, including the waters of the Arctic Ocean.

The point of the use of the NSNW, regardless of where it is exploded, would be to send a clear signal to the United States, NATO, and others who are supporting the Ukrainian political and military resistance that their generous backing must end—immediately.

If these supporters choose otherwise, the risk would be that Moscow might escalate from a single, low-yield nuclear “warning shot” on the battlefield or into an unpopulated area to using low-yield or high-yield theater or intercontinental-range strategic nuclear weapons, targeting populated areas in countries that back Ukraine, especially those that are part of NATO.

The Kremlin might calculate that Ukraine’s main supporters (e.g., the United States and NATO) do not have the political will to risk a wider conventional conflict with Russia or chance the possibility of a move up the nuclear-escalation ladder with Moscow that could result in all-out nuclear war and unspeakable carnage.

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Ukraine’s backers—and Ukraine itself— would also have to make some fateful choices on its response.

Using the escalate-to-deescalate nuclear stratagem, Moscow potentially could force any number of advantageous political and military outcomes to the war in Ukraine, including a victory that avoids the deep unpleasantries of a defeat and all that a loss would incur for Moscow domestically and internationally. 

Of course, the use of any nuclear weapon— strategic or tactical—in war for the first time since World War II is a troubling idea to contemplate, even one over an unpopulated area for the purposes of political-military signaling. But policymakers, analysts, and observers must understand that Russian political and military policy includes options for the possible use of the 2,000 tactical nuclear weapons in its nuclear arsenal.

Consequently, the United States and NATO must consider Russia’s use of tactical nuclear weapons in the Ukraine crisis a real possibility, especially as the length of the war increases. At this point, the possible use of battlefield nuclear weapons by Russia is arguably a “low risk,” but it is not a “no risk” scenario. It could happen.

As such, the United States and NATO must take the threat of Russian battlefield nuclear weapons very seriously, surveil the movement of Russian nuclear forces intensely, and prepare at the policy and military level for the possibility of a nuclear event, including the making of tough choices that a Russian nuclear event in Ukraine would bring.      

Beyond the Ukraine crisis, the United States, NATO, and other European partners must be thinking about Moscow’s advantage in NSNWs and its “escalate to deescalate” doctrine. The significant imbalance and potential willingness to use these weapons could encourage greater Russian risk-taking now and in the future, deeply undermining European security and U.S. and NATO interests. 

As we have seen repeatedly—from disinformation campaigns to cyberattacks to military operations overseas (e.g., Syria)—Russia will use every instrument of its national power to achieve its geopolitical goals. This state of affairs means that Russia’s small nukes are a potentially big problem for the United States, NATO, and its partners in Europe.