The ongoing Russia-Ukraine war escalated with North Korea’s (DPRK) troops deployed to Russia. The alarming situation poses a critical challenge to the United States and its allies and partners, raising an important question: is integrated deterrence failing? This was a central question at the Deterrence in the 2025 National Defense Strategy Review workshop, hosted by the Center for Global Security Research at the Lawrence Livermore National Laboratory. During the workshop, experts debated whether nuclear deterrence is still effective, what can be done to enhance deterrence capabilities, and how the U.S. and its allies should respond to adversaries—specifically the People’s Republic of China (PRC), Russia, the Democratic People’s Republic of Korea (DPRK), and Iran—moving forward.
Drawing on the discussions from the workshop, this paper argues that the U.S. and its allies should not focus solely on nuclear deterrence, but on a broader concept of deterrence that encompasses various strategies and tools to counter adversaries, including strengthening conventional military capabilities. Additionally, it highlights that a key component of this approach is enhancing communication channels, both among allies and partners, and with adversaries themselves. Below, I elaborate on what I learned from this deterrence workshop, and these reflections do not represent any particular organization.
Not Nuclear Deterrence, but just Deterrence
It is essential to conceptualize deterrence as a broad strategic goal, rather than narrowly focusing on nuclear deterrence, because the ultimate objective is to prevent adversaries from initiating any form of attack, not solely nuclear strikes. Nuclear deterrence cannot be considered in isolation from other forms of deterrence, including the prevention of conventional military actions and non-kinetic threats such as cyber, space, and information warfare. A robust approach to deterrence must encompass all domains of conflict, addressing various types of aggression with a comprehensive strategy that ensures resilience across all fronts.
The United States’ primary goal should be to prevent escalation to a full-scale nuclear exchange—essentially, prioritizing intra-war deterrence. In this context, it is crucial for the U.S. and its allies to enhance their conventional military capabilities, preparing for scenarios where non-nuclear means of warfare, such as conventional strikes, cyber operations, and technological threats, and misinformation campaigns, may be predominant. These daily, often incremental challenges may initially appear minor but, when accumulated, pose significant and multifaceted national security threats. Addressing these emerging risks is vital to maintaining stability and ensuring that deterrence remains effective across a spectrum of potential adversarial actions.
Deterrence from Whom and What?
The question of whom to deter is relatively straightforward: the adversaries of the United States and its allies and partners. Historically, this challenge was framed as a “two-peer” problem, primarily involving the combined strength of China and Russia. However, today’s strategic environment has evolved into a situation where the U.S. and its allies face adversaries that are increasingly collaborating across a diverse array of domains, often with greater speed, coordination, and complexity. A notable example of this shift is North Korea’s recent support for Russia by sending troops to Ukraine, likely in exchange for significant economic aid—estimated between $320 million and $1.3 billion annually. While this aid would provide a critical lifeline to North Korea’s heavily sanctioned and struggling economy, the more alarming aspect of this development is that the economic benefit may be secondary to the technological gains North Korea seeks from Russia, particularly in advancing its nuclear and missile capabilities. This poses a significant concern for South Korea. Such scenarios, where the U.S. and its allies must counter multiple, interconnected adversaries simultaneously, complicate strategic calculations, requiring the consideration of a range of potential outcomes and dynamic shifts in the geopolitical landscape.
Beyond adversary collaboration, the growing individual capabilities of certain actors, notably China, present an additional strategic concern. The rapid expansion of China’s power is alarming for the U.S. for several reasons, but most significantly because it threatens to alter the existing geopolitical status quo. China’s increasing engagement in global affairs, especially in regions traditionally influenced by the U.S., challenges the international order that Washington has shaped since the end of the Cold War. As China’s global influence grows, bolstered by its expanding economy, it reshapes the international system, undermining the liberal order championed by the U.S. and threatening America’s standing in global affairs.
This shift in power is further complicated by China’s political system, an authoritarian regime where decision-making is concentrated within a small circle of leaders that includes President Xi. Were China a more pluralistic society, its rise might not be perceived as such a direct challenge to U.S. interests. However, the concentration of power amplifies the risks associated with China’s ascension on the world stage. Moreover, China’s efforts to “export” its authoritarian model to other nations have contributed to a broader global backslide in democratic values, directly challenging the ideals that the U.S. has long sought to uphold in the international order.
Equally concerning is China’s rapid military modernization. According to the 2024 U.S. Department of Defense Annual Report, the People’s Liberation Army (PLA) has made substantial strides in modernizing its forces across all domains of warfare, including land, air, maritime, nuclear, space, counterspace, electronic warfare, and cyberspace. The PLA’s ambition is to evolve into a highly integrated, joint force capable of conducting a wide range of military operations at an accelerated pace. Of particular concern is the expansion of the PLA Navy (PLAN), which now boasts the largest naval fleet in the world, including over 370 ships and submarines, with more than 140 major surface combatants. Such rapid naval buildup has significantly enhanced China’s influence in critical maritime regions, particularly the South China Sea. This is where territorial disputes (especially with the Philippines, a key U.S. ally in the Indo-Pacific) have exacerbated tensions and further complicated regional security dynamics.
As such, the increasing military capabilities of individual adversaries, coupled with their growing collaborative actions, pose a direct challenge to U.S. interests. This trend undermines the broader balance of power in the Indo-Pacific region, shedding light on the need for more effective deterrence and counteraction strategies from the United States and its allies.
Restoring and Reassuring Deterrence: The Role of Communication and Signaling with Allies and Partners as well as Adversaries
The current geopolitical landscape reveals a significant erosion of deterrence strategies, as adversaries increasingly engage in cooperative actions and enhance their military capabilities, particularly in the realm of nuclear armament. This growing militarization, coupled with the modernization of nuclear forces, underscores the erosion of traditional nuclear deterrence. To address this challenge, it is imperative to revitalize deterrence through more effective communication and signaling. Clear, explicit communication with both allies and partners, as well as with adversaries, is essential to reestablishing stability and reinforcing deterrence. This approach will not only reassure allies but also convey unambiguous messages to adversaries regarding the potential consequences of escalation, thereby enhancing the credibility and effectiveness of deterrence strategies.
Integrated Deterrence with Allies and Partners by Ensuring They Share the Same Goals and Interests Through Further Communications
Deterrence is not achievable without the active cooperation of U.S. allies and partners. Unlike conventional military operations, which the U.S. can largely manage independently, countering advanced strike capabilities requires shared responsibility with allied nations. One critical contribution that allies and partners can provide is the development of industrial bases, leveraging their advanced manufacturing technologies and skilled human resources. Given the limitations of U.S. industrial capacity, collaboration through co-production is essential. For example, a RAND Corporation report on the industrial capabilities of the U.S. allies in quantum technology highlights that alongside the U.S. and China, Germany and the United Kingdom are among the leading nations in producing scientific research across the three main domains of quantum technology applications. The advanced technologies possessed by U.S. allies and partners demonstrate the potential for harmonizing and modernizing defense industrial bases, enabling these nations to rapidly co-develop, co-produce, and maintain interoperable systems capable of addressing emerging security threats.
However, while U.S. allies and partners generally share common interests and goals, it is crucial to recognize that these countries prioritize their own national interests, which can complicate cooperation if their priorities conflict with those of the U.S. Allies and partners are increasingly acquiring advanced conventional weapons, such as vessels and aircraft, enhancing their own independent military capabilities. This trend may lead to more separate decision-making processes, particularly when divergent interests arise. Consider the Republic of Korea (ROK) in the context of a potential Taiwan conflict. As a strong U.S. ally with U.S. military bases on its soil, South Korea has a vested interest in U.S. engagement in the region. While Seoul may favor a robust U.S. response to a Taiwan crisis to demonstrate Washington’s commitment to the Indo-Pacific and the alliance framework, it is also predictable that South Korea might prefer to avoid U.S. involvement in the Taiwan conflict. This is due to fear of potential destabilization on the Korean Peninsula, including the risk of U.S. force relocation and increased threats from North Korea. Additionally, economic coercion from Beijing, as seen in the 2017 deployment of the Terminal High Altitude Area Defense (THAAD) system, could further complicate South Korea’s position.
This dynamic demonstrates the complexity of ensuring alignment between the U.S. and allies’ interests. Allies and partners may not only seek to align their interests with those of the U.S., but may also seek to influence U.S. actions, either urging or discouraging particular moves, which could ultimately strain the alliance framework. Moreover, the alignment of interests can be further complicated by factors such as negotiations surrounding defense budgets, turbulence in domestic politics, including leadership changes, and changing national security priorities. With a diverse set of allies and partners, including key nations in the Indo-Pacific—such as Japan, South Korea, and the Philippines— as well as European allies through NATO, it is essential for the U.S. to effectively consolidate their goals by accurately reflecting their interests through clear, coordinated messaging.
To facilitate this process, the establishment of integrated decision-making mechanisms, whether bilateral or multilateral, should be prioritized. These groups would enable real-time communication and foster mutual understanding of each nation’s interests, ensuring better preparation and responsiveness in the event of conflicts. This approach would enhance the cohesion and effectiveness of the alliance framework, ensuring that shared deterrence objectives are maintained even in the face of complex and shifting geopolitical dynamics.
Enhancing Deterrence Through Clear Communication: Addressing the Challenges of a Four-Peer Adversarial Landscape
Similarly, addressing a more diversified set of adversaries requires the U.S. and its allies to deliver clear, deliberate messages in a manner that ensures their intended meaning is understood. As aforementioned, in contrast to the Cold War era, when adversarial interactions were primarily characterized by a “two-peer” dynamic, the growing cooperation among China, North Korea, Russia, and Iran presents a far more complex challenge. This collaboration has effectively transformed the situation into a “four-peer” problem, complicating strategic calculations and increasing the potential for misunderstandings and miscalculations. While immediate responses, such as enhanced analytical efforts and expanded wargaming exercises, are essential, addressing the core issue of inadequate communication remains critical. To mitigate the risk of miscommunication and misunderstanding, it is imperative to prioritize more frequent and substantive consultations between leaders and officials, including military-to-military dialogues. Strengthening engagement through clear, explicit communication will be essential to ensure that messages are accurately understood, preventing unnecessary escalations and fostering more effective coordination among allies and adversaries alike.
Conclusion
While nuclear deterrence remains a critical pillar of the U.S. defense strategy, it cannot be the sole focus. Deterrence today must encompass a broad spectrum of capabilities—spanning conventional military power, cyber defenses, space capabilities, economic sanctions, and even information operations. As the world becomes more interconnected and adversaries collaborate more effectively, the U.S. must broaden its strategic outlook, ensuring that all potential avenues of aggression—whether kinetic, non-kinetic, or hybrid—are addressed through a unified and coherent deterrence framework.
Key to this broader deterrence strategy is the integration of efforts with U.S. allies and partners. Deterrence cannot be achieved unilaterally; it requires close coordination, shared responsibilities, and the joint development of military and technological capabilities. By leveraging the strengths of allies, particularly in areas like quantum technologies and advanced manufacturing, the U.S. can modernize and strengthen its own deterrence posture while ensuring that alliances remain resilient and adaptable in the face of emerging threats. However, effective integration requires more than just technological cooperation—it demands a deliberate, continuous process of consultation, signaling, and alignment of interests among partners. As evidenced by the challenges posed in regions like the Indo-Pacific, where divergent national interests can complicate decision-making, maintaining a clear and unified approach is essential.
Moreover, clear and credible messaging to adversaries will be crucial in avoiding misunderstandings and preventing the escalation of conflicts. Whether through direct military-to-military dialogues, diplomatic engagements, or public signaling, the U.S. must prioritize transparent communication that reinforces the credibility of its deterrent threats to adversaries.
In conclusion, by broadening deterrence beyond nuclear weapons to include conventional, cyber, and diplomatic elements, and by ensuring that communication channels remain open and effective, the U.S. can maintain stability, prevent escalation, and safeguard its interests in an increasingly unpredictable world.
Sheewon Min is a Research Associate at the East Asia Institute (EAI), a Seoul-based think tank. Her research primarily focuses on the Indo-Pacific region, with particular attention to Beijing’s economic statecraft, the U.S. alliance framework, and the foreign policy strategies of middle-power countries in the context of U.S.-China strategic competition. She is also a member of the Pacific Forum’s Young Leaders Program and serves as a non-resident Vasey Fellow at the Institute. Sheewon holds a Master’s degree in Asian Studies from Georgetown University, where she specialized in international political economy, politics, and security. She earned her B.A. in Asian Studies from Yonsei University, graduating one year early with honors.
Disclaimer: All opinions in this article are solely those of the author and do not represent any organization.
Photo: A Terminal High Altitude Area Defense interceptor missile launches during a flight test at the Ronald Reagan Ballistic Missile Defense Test Site in the Marshall Islands, Aug., 30, 2019. Source: Courtesy photo from DoD
