In July 2024 Norway’s Kongsberg Defence & Aerospace signed a contract with the Norwegian Defence Materiel Agency (NDMA) for the development of a next-generation ‘supersonic strike missile’, as part of a collaborative project between Norway and Germany first announced in November 2023. The plan is for the new manoeuvrable naval strike missile, dubbed the Tyrfing, to be operational in 2035.
This is just one of several recent high-profile efforts involving Nordic states that aim to enhance European conventional capabilities in order to deter aggression and maintain strategic stability. Others include Finland’s announcement, in May 2024, that it is acquiring Joint Air-to-Surface Standoff Missile-Extended Range (JASSM-ER) weapons from the United States, which comes on top of its 2021 order of US F-35 combat aircraft. Around the same time, Sweden announced that it would provide Ukraine with early warning and control aircraft equipped with its Erieye radar system. This is expected to represent a ‘big force multiplier’ for Ukraine’s F-16 combat aircraft.
These moves in the Nordic region reflect broader European trends in the development and deployment of advanced conventional precision-strike capabilities. Investments in longer-range, manoeuvrable missiles and delivery systems—including the Tyrfing and the planned deployment on German soil of US hypersonic systems and ground-launched missiles that would have been prohibited under the now-defunct Intermediate-Range Nuclear Forces Treaty (INF Treaty)—contribute to the spectre of a ‘new missile crisis’ in Europe. Planned upgrades to European global navigation satellite systems (GNSS) will further bolster the ability of these weapon systems to rapidly locate, target and ultimately destroy targets.
For the Nordic states, and especially for new NATO members Finland and Sweden, Russia’s war in Ukraine has provided clear justification for such developments. They are seeking both to demonstrate solidarity with other NATO members and to strengthen the alliance’s conventional capabilities in order to complement the extended US nuclear deterrent. But these decisions have many implications—and come with risks—that European policymakers may not have fully considered.
Advanced conventional capabilities as a source of instability
Conventional precision-strike weapon systems were first employed in significant numbers by the USA during the 1990–91 Gulf War. They have matured significantly since then, enabled by a combination of improved guidance, advances in warhead technology, and vastly better intelligence, surveillance and reconnaissance capabilities. Furthermore, whereas the USA possessed the vast majority of these weapons at the end of the cold war, many states now have or are planning to acquire them in large numbers.
Although precision-strike systems have numerous functions in conventional warfare, they can also impact strategic stability and nuclear deterrence dynamics. This is because they can threaten nuclear-related targets such as hardened missile silos and command-and-control nodes to a much greater extent than their predecessors.
Some states have already started leveraging this fact. For example, South Korea has, since 2012, employed a deterrence strategy that targets North Korean nuclear forces with a large arsenal of air-, land- and sea-based precision-strike conventional weapons. In response, North Korea is ‘designing around’ South Korea’s deterrence strategy by developing a large number of nuclear-capable short-range missiles and other delivery systems. While having a small nuclear arsenal—an estimated 50 warheads—features prominently in North Korea’s strategic calculus, the case gives some indication of how other nuclear-armed states may react to conventional developments.
The potential risks fall into two main categories. First, the development and deployment of advanced conventional precision-strike capabilities may accelerate arms racing. All nuclear-armed states will increasingly take their adversaries’ conventional capabilities into consideration when developing their force structures and postures—a function of technological realities. This is especially pertinent with the potential deployment of NATO precision-strike capabilities in Finland and Sweden, near key Russian nuclear sites such as the ballistic missile submarine facilities on the Kola Peninsula or the strategic bombers located at Olenya airbase (just 150 kilometres from the Finnish border, and reportedly the target of a Ukrainian attack in July 2024).
Even if they do not intend to target them at Russian nuclear sites, Nordic states need to consider how conventional weapons and capabilities they are developing might affect the strategic calculus of Russia and its allies. For example, following the 2024 announcement that the USA plans to deploy longer-range and hypersonic missiles in Germany, President Vladimir Putin promised ‘mirror measures’ and Russia has since used its Oreshnik intermediate-range ballistic missile system in Ukraine, with Russian officials noting the lack of treaty restrictions on its deployment.
Second, increased precision-strike capabilities could have negative effects on crisis stability. For instance, during a crisis a nuclear-armed state may mistakenly believe that a conventional attack with precision-strike weapons is targeted at its nuclear forces, creating pressure to use them rather than risk losing them. In addition, the steps that states take to bolster the survivability of their nuclear forces in the face of growing conventional threats, such as raising alert levels, may increase the potential for escalation. These risks are likely to be more pronounced in crises involving states with small and potentially vulnerable nuclear arsenals, such as North Korea. However, NATO member states cannot ignore them even in relation to Russia.
Reconsidering strategic stability in arms control
The constellation of past bilateral nuclear arms control agreements between the Soviet Union/Russia and the USA was founded on notions of ‘strategic stability’—a fragile balance based on a shared need to maintain the assurance of nuclear retaliation. Advanced conventional systems increasingly threaten these retaliatory capabilities and, accordingly, the adversaries’ confidence that the strategic relationship is stable. The ramifications of this already seem to be affecting the prospects for arms control dialogue. Notably, Russia refuses to discuss resuming the New Strategic Arms Reduction Treaty (New START), which has been suspended since 2023, expressing a strong preference for considering ‘other elements of strategic security’ in negotiations, as well as involving other European states.
The development and deployment of advanced conventional capabilities could complicate future efforts to rebuild the nuclear arms control architecture more broadly. Any future arms control framework will likely have to reconsider what capabilities are strategic, and potentially incorporate the conventional capabilities of non-nuclear-armed states.
In 2021—months before Russia’s full-scale invasion of Ukraine—Russia and the USA established a working group on ‘capabilities and actions with strategic effects’ as part of their now-paused strategic stability dialogue. This suggested mutual recognition of the strategic importance of certain conventional weapon systems. The recent update of Russian nuclear doctrine to include possible nuclear use in response to aggression from non-nuclear-armed states involving or supported by a nuclear-armed state reinforces the blurring of boundaries between conventional and nuclear capabilities.
Perhaps the fundamental issue is that strategic stability, already elusive during the cold war, appears even more difficult to achieve in a multipolar world. The different ways in which nuclear forces are being made vulnerable, including by precision-strike weapons but also through the development of and technological advances in cyber and counterspace capabilities, means that the incentives for first use of nuclear weapons may be increasing, especially in conflict or crisis situations. The blurring of the conventional–nuclear distinction may not only be removing the unique status of nuclear weapons but also have as yet unexplored consequences for the nuclear taboo, as suggested by Putin’s nuclear sabre-rattling in response to the activities of non-nuclear-armed states.
Understanding and ensuring intended deterrent effects
All of this calls into question the assumptions on which decisions by Nordic states are seemingly being made. Even if advanced conventional capabilities form—alongside political unity—‘the most significant source of NATO’s deterrent power’, the continued maturation and proliferation of those capabilities have far-reaching consequences, including for nuclear strategies, nuclear force structures and even nuclear use. To avoid worst-case scenarios, three interrelated points should be considered by Nordic, as well as other European, states before they make further investments in such capabilities.
First, these states should continually and carefully assess the potential consequences of the development and deployment of advanced conventional capabilities. This process should start with systematic consideration of how they alter the conventional balance, but it should also encompass how these activities align with underlying threat perceptions, including those of Russia and its allies, and the potential impacts on nuclear deterrence dynamics.
The process should also involve ensuring that any signalling—of resolve, restraint or readiness—that the deployment of new conventional capabilities is meant to do is coherent internally (including among allies) and clear externally. Even if this does not change the deployment decisions, it can at least reduce the risk of unintended consequences.
Second, these states should also account in their security strategies for the nature and impact of blurring boundaries between conventional and nuclear capabilities. This necessitates careful analysis of how others perceive ‘strategic’ effects—technologically, materially and militarily, as well as politically. For instance, both China and Russia have rejected US diplomatic efforts to compartmentalize nuclear arms control from the broader strategic context. Challenging the traditional boundaries of concepts such as ‘strategic effect’ and moving beyond cold war-era frames of reference may enable greater understanding among Nordic and other European states of the wider consequences of their national-level decisions in the conventional realm, while facilitating innovative and less risky policy solutions, including arms control.
Finally, Nordic and other European states should revisit their fundamental assumptions around nuclear deterrence. This includes critically examining the claims often presented by nuclear-armed states as to what nuclear capabilities successfully deter. This is especially pertinent given the discourse about deterrence in Europe connected to the war in Ukraine. The list of behaviours that nuclear weapons have historically been said to have deterred is long, and is an important factor in justifying nuclear modernization plans.
As Nordic states take steps to strengthen NATO’s nuclear deterrence, they could consider engaging in discussions in venues that more openly acknowledge the complexities and explore the risks related to the deterrence paradigm. These include the recent findings of expert networks, or the ongoing work by states parties to the Treaty on the Prohibition of Nuclear Weapons to research ‘risks and assumptions that are inherent in nuclear deterrence’.
Dispelling myths and specifying exactly when and how deterrence works can pave the way for more effective means to pursue national security objectives, including through non-military solutions, while minimizing the risk of further destabilization and potential escalation.
The authors would like to acknowledge the contributions of Henrik Hiim and Tytti Erästö, as well as insights provided by Nordic-based participants in two exploratory workshops on ‘WMD understandings, governance and technology’ convened at SIPRI in June 2023 and September 2024 as part of work funded by the Joint Committee for Nordic research councils in the Humanities and Social Sciences (NOS-HS).
Accurate, dependable information is more important than ever. Invest in the facts. Support SIPRI.
ABOUT THE AUTHOR(S)
Dr Wilfred Wan is the Director of the SIPRI Weapons of Mass Destruction Programme.
Dr Gitte du Plessis is an Academy of Finland Research Fellow based at Oulu University.
In July 2024 Norway’s Kongsberg Defence & Aerospace signed a contract with the Norwegian Defence Materiel Agency (NDMA) for the development of a next-generation ‘supersonic strike missile’, as part of a collaborative project between Norway and Germany first announced in November 2023. The plan is for the new manoeuvrable naval strike missile, dubbed the Tyrfing, to be operational in 2035.
This is just one of several recent high-profile efforts involving Nordic states that aim to enhance European conventional capabilities in order to deter aggression and maintain strategic stability. Others include Finland’s announcement, in May 2024, that it is acquiring Joint Air-to-Surface Standoff Missile-Extended Range (JASSM-ER) weapons from the United States, which comes on top of its 2021 order of US F-35 combat aircraft. Around the same time, Sweden announced that it would provide Ukraine with early warning and control aircraft equipped with its Erieye radar system. This is expected to represent a ‘big force multiplier’ for Ukraine’s F-16 combat aircraft.
These moves in the Nordic region reflect broader European trends in the development and deployment of advanced conventional precision-strike capabilities. Investments in longer-range, manoeuvrable missiles and delivery systems—including the Tyrfing and the planned deployment on German soil of US hypersonic systems and ground-launched missiles that would have been prohibited under the now-defunct Intermediate-Range Nuclear Forces Treaty (INF Treaty)—contribute to the spectre of a ‘new missile crisis’ in Europe. Planned upgrades to European global navigation satellite systems (GNSS) will further bolster the ability of these weapon systems to rapidly locate, target and ultimately destroy targets.
For the Nordic states, and especially for new NATO members Finland and Sweden, Russia’s war in Ukraine has provided clear justification for such developments. They are seeking both to demonstrate solidarity with other NATO members and to strengthen the alliance’s conventional capabilities in order to complement the extended US nuclear deterrent. But these decisions have many implications—and come with risks—that European policymakers may not have fully considered.
Advanced conventional capabilities as a source of instability
Conventional precision-strike weapon systems were first employed in significant numbers by the USA during the 1990–91 Gulf War. They have matured significantly since then, enabled by a combination of improved guidance, advances in warhead technology, and vastly better intelligence, surveillance and reconnaissance capabilities. Furthermore, whereas the USA possessed the vast majority of these weapons at the end of the cold war, many states now have or are planning to acquire them in large numbers.
Although precision-strike systems have numerous functions in conventional warfare, they can also impact strategic stability and nuclear deterrence dynamics. This is because they can threaten nuclear-related targets such as hardened missile silos and command-and-control nodes to a much greater extent than their predecessors.
Some states have already started leveraging this fact. For example, South Korea has, since 2012, employed a deterrence strategy that targets North Korean nuclear forces with a large arsenal of air-, land- and sea-based precision-strike conventional weapons. In response, North Korea is ‘designing around’ South Korea’s deterrence strategy by developing a large number of nuclear-capable short-range missiles and other delivery systems. While having a small nuclear arsenal—an estimated 50 warheads—features prominently in North Korea’s strategic calculus, the case gives some indication of how other nuclear-armed states may react to conventional developments.
The potential risks fall into two main categories. First, the development and deployment of advanced conventional precision-strike capabilities may accelerate arms racing. All nuclear-armed states will increasingly take their adversaries’ conventional capabilities into consideration when developing their force structures and postures—a function of technological realities. This is especially pertinent with the potential deployment of NATO precision-strike capabilities in Finland and Sweden, near key Russian nuclear sites such as the ballistic missile submarine facilities on the Kola Peninsula or the strategic bombers located at Olenya airbase (just 150 kilometres from the Finnish border, and reportedly the target of a Ukrainian attack in July 2024).
Even if they do not intend to target them at Russian nuclear sites, Nordic states need to consider how conventional weapons and capabilities they are developing might affect the strategic calculus of Russia and its allies. For example, following the 2024 announcement that the USA plans to deploy longer-range and hypersonic missiles in Germany, President Vladimir Putin promised ‘mirror measures’ and Russia has since used its Oreshnik intermediate-range ballistic missile system in Ukraine, with Russian officials noting the lack of treaty restrictions on its deployment.
Second, increased precision-strike capabilities could have negative effects on crisis stability. For instance, during a crisis a nuclear-armed state may mistakenly believe that a conventional attack with precision-strike weapons is targeted at its nuclear forces, creating pressure to use them rather than risk losing them. In addition, the steps that states take to bolster the survivability of their nuclear forces in the face of growing conventional threats, such as raising alert levels, may increase the potential for escalation. These risks are likely to be more pronounced in crises involving states with small and potentially vulnerable nuclear arsenals, such as North Korea. However, NATO member states cannot ignore them even in relation to Russia.
Reconsidering strategic stability in arms control
The constellation of past bilateral nuclear arms control agreements between the Soviet Union/Russia and the USA was founded on notions of ‘strategic stability’—a fragile balance based on a shared need to maintain the assurance of nuclear retaliation. Advanced conventional systems increasingly threaten these retaliatory capabilities and, accordingly, the adversaries’ confidence that the strategic relationship is stable. The ramifications of this already seem to be affecting the prospects for arms control dialogue. Notably, Russia refuses to discuss resuming the New Strategic Arms Reduction Treaty (New START), which has been suspended since 2023, expressing a strong preference for considering ‘other elements of strategic security’ in negotiations, as well as involving other European states.
The development and deployment of advanced conventional capabilities could complicate future efforts to rebuild the nuclear arms control architecture more broadly. Any future arms control framework will likely have to reconsider what capabilities are strategic, and potentially incorporate the conventional capabilities of non-nuclear-armed states.
In 2021—months before Russia’s full-scale invasion of Ukraine—Russia and the USA established a working group on ‘capabilities and actions with strategic effects’ as part of their now-paused strategic stability dialogue. This suggested mutual recognition of the strategic importance of certain conventional weapon systems. The recent update of Russian nuclear doctrine to include possible nuclear use in response to aggression from non-nuclear-armed states involving or supported by a nuclear-armed state reinforces the blurring of boundaries between conventional and nuclear capabilities.
Perhaps the fundamental issue is that strategic stability, already elusive during the cold war, appears even more difficult to achieve in a multipolar world. The different ways in which nuclear forces are being made vulnerable, including by precision-strike weapons but also through the development of and technological advances in cyber and counterspace capabilities, means that the incentives for first use of nuclear weapons may be increasing, especially in conflict or crisis situations. The blurring of the conventional–nuclear distinction may not only be removing the unique status of nuclear weapons but also have as yet unexplored consequences for the nuclear taboo, as suggested by Putin’s nuclear sabre-rattling in response to the activities of non-nuclear-armed states.
Understanding and ensuring intended deterrent effects
All of this calls into question the assumptions on which decisions by Nordic states are seemingly being made. Even if advanced conventional capabilities form—alongside political unity—‘the most significant source of NATO’s deterrent power’, the continued maturation and proliferation of those capabilities have far-reaching consequences, including for nuclear strategies, nuclear force structures and even nuclear use. To avoid worst-case scenarios, three interrelated points should be considered by Nordic, as well as other European, states before they make further investments in such capabilities.
First, these states should continually and carefully assess the potential consequences of the development and deployment of advanced conventional capabilities. This process should start with systematic consideration of how they alter the conventional balance, but it should also encompass how these activities align with underlying threat perceptions, including those of Russia and its allies, and the potential impacts on nuclear deterrence dynamics.
The process should also involve ensuring that any signalling—of resolve, restraint or readiness—that the deployment of new conventional capabilities is meant to do is coherent internally (including among allies) and clear externally. Even if this does not change the deployment decisions, it can at least reduce the risk of unintended consequences.
Second, these states should also account in their security strategies for the nature and impact of blurring boundaries between conventional and nuclear capabilities. This necessitates careful analysis of how others perceive ‘strategic’ effects—technologically, materially and militarily, as well as politically. For instance, both China and Russia have rejected US diplomatic efforts to compartmentalize nuclear arms control from the broader strategic context. Challenging the traditional boundaries of concepts such as ‘strategic effect’ and moving beyond cold war-era frames of reference may enable greater understanding among Nordic and other European states of the wider consequences of their national-level decisions in the conventional realm, while facilitating innovative and less risky policy solutions, including arms control.
Finally, Nordic and other European states should revisit their fundamental assumptions around nuclear deterrence. This includes critically examining the claims often presented by nuclear-armed states as to what nuclear capabilities successfully deter. This is especially pertinent given the discourse about deterrence in Europe connected to the war in Ukraine. The list of behaviours that nuclear weapons have historically been said to have deterred is long, and is an important factor in justifying nuclear modernization plans.
As Nordic states take steps to strengthen NATO’s nuclear deterrence, they could consider engaging in discussions in venues that more openly acknowledge the complexities and explore the risks related to the deterrence paradigm. These include the recent findings of expert networks, or the ongoing work by states parties to the Treaty on the Prohibition of Nuclear Weapons to research ‘risks and assumptions that are inherent in nuclear deterrence’.
Dispelling myths and specifying exactly when and how deterrence works can pave the way for more effective means to pursue national security objectives, including through non-military solutions, while minimizing the risk of further destabilization and potential escalation.
The authors would like to acknowledge the contributions of Henrik Hiim and Tytti Erästö, as well as insights provided by Nordic-based participants in two exploratory workshops on ‘WMD understandings, governance and technology’ convened at SIPRI in June 2023 and September 2024 as part of work funded by the Joint Committee for Nordic research councils in the Humanities and Social Sciences (NOS-HS).
Accurate, dependable information is more important than ever. Invest in the facts. Support SIPRI.
ABOUT THE AUTHOR(S)