The nuclear mission of the North Atlantic Treaty Organization (NATO) is a legacy of the Cold War as currently postured. The weapons are stored in Belgium, Germany, Italy, Türkiye, and the Netherlands—far from Russia’s borders.REF

Poland’s prime minister recently requested to be part of the NATO mission, known as nuclear burden sharing, that stores and may deliver nuclear weapons in times of crisis. While there would be costs and benefits to such a development that need to be weighed, Poland’s proposal is a serious one and may provide NATO with the long-overdue opportunity to strengthen deterrence in Europe through an updated nuclear posture.

What Is NATO Nuclear Burden Sharing?

In the nuclear burden-sharing mission, a small number of American nuclear gravity bombs are stationed at NATO bases in Europe. Allied pilots are trained to drop the nuclear weapons by American instructors and fly their nations’ nuclear-capable fighter bombers in such training activities. The weapons are stored in highly secure weapons-storage sites and may be employed only through the consent of the NATO North Atlantic Council and the American commander in chief.

In short, these are American weapons that allied pilots can deliver in times of extreme danger in Europe. Other NATO allies fly conventional support operations, including counter-air operations, refueling, suppression of enemy air defenses, and others. But as of today, only those states that joined NATO before the fall of the Berlin Wall store and may deliver American nuclear weapons under the NATO burden-sharing agreement.REF

The goals of the mission, which originated in the Cold War, are to deter aggression, particularly nuclear aggression, against NATO allies (presumably by Russia); assure allies that the American nuclear guarantee is credible; strengthen the alliance politically by making the nuclear-strike mission an alliance-wide activity; and signal resolve that NATO will not be intimidated by nuclear coercion. This is all done, in part, by providing a visible, geographic distribution and demonstration of NATO’s nuclear capabilities.

On June 30, 2023, following the conclusion of a two-day European Council summit, Polish Prime Minister Mateusz Morawiecki held a press conference at which he said that “in connection with the fact that Russia intends to deploy tactical nuclear weapons in Belarus, we ask the entire NATO to take part in the nuclear sharing program.”REF

He went on to say that “the final decision will depend on our American and NATO partners. We declare our will to act quickly…. We do not want to sit idly by while [Russian President Vladimir] Putin builds up his threats of various kinds.”REF Later that day, U.S. National Security Council spokesman John Kirby responded to the prime minister’s request by saying, “I have nothing to say about any conversations of this type. And, either way, we’re just not talking about deploying our nuclear systems, so I’m certainly not going to start doing that today.”REF With such a short, off-the-cuff comment, it seems that the White House dismissed the request out of hand without giving it any meaningful consideration.

The Costs of Polish Participation in Nuclear Burden Sharing

The Polish proposal is a serious one, although it has significant ramifications for U.S. and NATO security. It deserves serious consideration.

To begin with, there are real costs associated with nuclear burden sharing that must be acknowledged and addressed. The first of these is the financial cost associated with such a mission expansion. The cost of building nuclear-grade munitions-storage locations—along with the layered security and nuclear-surety procedures on par with those in Western European nuclear-storage sites—would be significant, potentially in the hundreds of millions of dollars. Typically, host nations bear most of the burdens of such infrastructure development, but there is a multi-billion-dollar NATO common fund budget that would likely offset some of these costs.REF

The training of the additional security forces would also be expensive, as would the training of pilots to deliver nuclear munitions. While Poland has ordered 32 F-35s, some subset of these would have to be converted and certified as nuclear-capable.REF But this would incur very minor additional costs,REF and it is very possible that the Polish government would cover such expenses, given Poland’s massive defense budget expansion.REF

Perhaps the most profound downside of Polish participation in the mission is the unpredictable reaction from Russia. Given the increasing talk among Moscow security elites of escalating the Ukraine conflict to include potential nuclear escalation,REF it is difficult to predict the Russian reaction to such a movement, which could, in the extreme case, include some type of kinetic response toward Poland, which is of course a NATO member.

The Benefits of Polish Participation in Nuclear Burden Sharing

The benefits of Poland hosting nuclear weapons align with the initial reasons for and continued benefits of forward basing American nuclear weapons in European states. In the Cold War, nuclear storage sites were near the front lines between NATO and the Warsaw Pact. This meant that NATO aircraft would be able to strike Soviet and Warsaw Pact targets quickly should the Soviets invade NATO states.REF These weapons, the vast majority of which were low-yield and designed to destroy not cities but Warsaw Pact troop formations, were meant to provide a credible counter to the Warsaw Pact’s military quantitative might and thereby convince the Soviet Union not to invade Western Europe. They were, in effect, tools of deterrence.

This logic, which was effective in the Cold War, remains applicable today. Fighter bombers armed with low-yield nuclear weapons remain a political tool. They are meant to deter aggression by presenting a credible combination of will and capability. Forward basing such systems in the eastern parts of NATO would demonstrate a credible and stable deterrent posture.

While some might argue that placing those systems in Poland would be an escalation by NATO,REF the reality is that NATO crafts its nuclear posture as it deems necessary to deter threats. NATO’s nuclear posture is informed by, but is ultimately independent of, decisions made by Moscow. NATO is a nuclear alliance that can and should do whatever it deems necessary to maintain a credible nuclear deterrent independent of where Russia bases its weapons. In addition, given that Russia announced in July that it moved some of its nuclear weapons into Belarus, a reciprocal announcement that NATO is considering a re-posturing of its own nuclear forces should not be seen by Moscow as provocative or escalatory.REF

One reason the United States shared nuclear weapons with NATO allies in the Cold War was to stave off a looming wave of proliferation. In 1963, following Britain and France becoming nuclear powers, Secretary of Defense Robert McNamara informed President John Kennedy that the number of nuclear weapon states could triple within 10 years and quintuple within 15 years.REF The idea of providing American nuclear weapons to NATO allies (under American-designed safeguards and oversight and releasable only with the authority of the American President and the North Atlantic Council) in part was to assure them that the American nuclear umbrella was viable, robust, and effective—and thus obviate their need for an independent nuclear capability.

As a nonproliferation tool, nuclear burden sharing proved effective. It helped stem the proliferation that McNamara warned about and reduced the number of potential nuclear weapons states. As Russia today rattles the nuclear saber and threatens NATO states with nuclear strikes,REF it is reasonable that NATO allies would want to be assured of the efficacy of the American nuclear umbrella. Expanding the nuclear burden-sharing mission to Poland or other states could address those concerns and potentially stave off nascent interest in an indigenous nuclear weapons capability, particularly among those NATO states closest to Russia.

Most importantly, expanding the nuclear burden-sharing mission to those states that joined NATO after the end of the Cold War would signal that NATO is not a moribund institution, unable to adapt to changing threat environments. It would show quite the opposite: that NATO can adapt to changes in the security environment in meaningful ways.

There are some indications that the Belgian, Dutch, and German populations are sympathetic to the nuclear global zero movement that seeks to abolish all nuclear weapons in the world.REF According to a 2020 survey, only a quarter of Dutch and Germans supported American nuclear bombs remaining in the two hosting countries no matter what.REF While more recent polls indicate that the Russian invasion of Ukraine has resulted in a decline in support for the withdrawal of American nuclear weapons from the continent, pollsters suggest that this change could “turn out to be a merely short-lived spike in public opinion rather than a lasting latitudinal change in individuals.”REF

Stationing nuclear weapons in bases in Belgium, Germany, Italy, Türkiye, and the Netherlands made sense during the Cold War: Those nations were near the “front lines” of the Warsaw Pact–NATO standoff. However, with the breakup of the Soviet empire and enlargement of NATO to the Baltics, Finland, and Poland, those bases are now several hundred miles farther from Russian forces. If such distances require a fighter bomber to conduct an aerial refueling before reaching a target, both the fighter bomber and the refueler could be vulnerable to enemy long-range air defenses.

Moving some nuclear weapons out of Germany, the Netherlands, and, potentially, Belgium and into NATO allies closer to Russia—say, Finland, Poland, and Romania—could accomplish three things simultaneously: (1) reduce a point of friction caused by the presence of nuclear weapons in Belgium, Germany, and the Netherlands; (2) assure those NATO allies closest to Russia that the arsenal remains credible and effective; and (3) better dissuade Russian aggression by increasing the relevance of the nuclear deterrent. Indeed, should a state such as Belgium or the Netherlands ask the United States at some future point to remove its nuclear weapons from its soil, having Poland or another Eastern European NATO ally prepared to take over that state’s nuclear burden-sharing responsibility might be a prudent risk-mitigation measure.

Given the lack of Russian threat to NATO in the 20 years after the end of the Cold War, it was unnecessary to change the nuclear burden-sharing status quo. But as Russia increasingly engages in provocative and dangerous behavior (to include its repeated attempts at nuclear coercion against NATO states), the expansion of the nuclear burden-sharing mission to the east could signal to Russia that NATO remains a dynamic and resilient organization that can adapt to new threats and maintain its security.

Toward a More Adaptive and Credible Deterrent

It should be noted that NATO’s Vilnius Summit Communique, issued in July 2023, indicated that NATO is ready to consider a more adaptive and flexible nuclear profile:

NATO will take all necessary steps to ensure the credibility, effectiveness, safety and security of the nuclear deterrent mission. This includes continuing to modernize NATO’s nuclear capability and updating planning to increase flexibility and adaptability of the Alliance’s nuclear forces…. The Alliance reaffirms the imperative to ensure the broadest possible participation by Allies concerned in NATO’s nuclear burden-sharing arrangements to demonstrate Alliance unity and resolve.REF

Therefore, the U.S. Departments of Defense and State, in conjunction with the NATO Nuclear Planning Group, should ensure that NATO’s deterrent posture is optimized to address 21st-century challenges. To wit, they should:

• Examine current deterrence requirements. This effort should include an analysis of updated capabilities and nuclear postures in order to ensure flexibility, adaptability, and, ultimately, the credibility of NATO’s nuclear forces.
• Analyze the pros and cons of expanding and/or reassigning the nuclear burden-sharing mission. The Vilnius Summit Communique provided guidance to NATO’s planning staff regarding the broadening of the nuclear burden-sharing mission, but NATO staff cannot do this work alone. The U.S. Departments of State and Defense should support this analysis.
• Consult with existing alliance members on their long-term desire to participate in the burden-sharing mission. NATO staff members and planners should use the Polish prime minister’s request as well as the Vilnius Communique as an opportunity to engage with alliance members who wish to reduce their roles in the nuclear burden-sharing mission. This is not to presuppose any specific outcome, such as the removal of nuclear weapons from legacy nuclear burden-sharing alliance members, but any re-posturing of NATO’s nuclear deterrent should incorporate the views of not only those who wish to join the nuclear mission but also those who may wish to reduce their roles in such a mission.

The Path Forward

The Polish request to take a central role in NATO’s nuclear burden sharing mission is worthy of consideration and should be examined with the utmost seriousness. Kirby’s seemingly out-of-hand dismissal of the proposal should not be the last word on the topic. The U.S. Mission to NATO should bring this issue up in discussions with the NATO Nuclear Planning Group for further analysis. Congress, through the National Defense Authorization Act, should at the same time request that the Air Force identify the impacts to deterring Russian aggression of such a re-posturing of NATO nuclear forces. The stakes are too great to do otherwise—and the time to modernize NATO’s decades-old deterrent posture may be here.

Robert Peters is Research Fellow for Nuclear Deterrence and Missile Defense in the Center for National Defense at The Heritage Foundation.