Introduction

Russia’s recent deployment of a conventionally armed, diesel-powered submarine to Indonesia should not be dismissed as routine naval activity. It is a calculated strategic signal. One that highlights a growing challenge for Australia and calls into question the resilience of U.S. extended deterrence in the Indo-Pacific. While such deployments fall below the nuclear threshold, they reveal an emerging approach to strategic competition. The use of advanced conventional capabilities can undermine the systems that enable nuclear deterrence.

At the center of this challenge is the vulnerability of U.S. nuclear command, control, and communications (NC3) architecture. Facilities in Australia, including Pine Gap and Naval Communication Station Harold E. Holt, are integral to this architecture. They support early warning, signals intelligence, and communications with nuclear forces. As such, they are not only strategic assets but also potential targets. Modern diesel-electric submarines—quiet, survivable, and increasingly capable—can operate in Australia’s northern approaches and threaten these critical nodes with precision strike options or intelligence-gathering missions that enable future disruption.

The Gray Zone Effect

This development reflects a broader shift in adversary strategy. Rather than relying on overt nuclear coercion, states such as Russia are exploring how to achieve strategic effects through conventional means. By targeting NC3 infrastructure using submarines, cyber operations, or long-range precision strike, adversaries can degrade the credibility of nuclear deterrence without crossing the nuclear threshold. This approach exploits the grey zone between peace and war, complicates escalation dynamics, and introduces ambiguity into alliance responses. It is not escalation dominance in the traditional sense, but escalation manipulation, and shaping the environment so that nuclear deterrence becomes less certain, less credible, and therefore less effective.

Recent Chinese naval activity reinforces this concern. The PLA Navy’s circumnavigation of Australia should not be viewed as routine presence or symbolic signaling alone. Rather, it demonstrates an emerging capacity to operate persistently along Australia’s littoral approaches and key maritime choke points—areas proximate to critical infrastructure that underpins U.S. and allied NC3. Such operations enable the mapping of undersea terrain, surveillance of communication pathways, and potential identification of vulnerabilities in systems such as subsea cables and relay nodes. In a crisis, these capabilities could be leveraged to conduct limited, deniable disruption of NC3 functions that degrade communication, delay decision-making, and complicate alliance coordination without crossing the threshold of armed attacks. In this sense, China’s activity mirrors and reinforces the broader trend: the use of conventional means to hold at risk the foundations of nuclear deterrence.

For Australia, the implications are significant. The traditional model of U.S. extended deterrence, anchored in the threat of nuclear retaliation, assumes that nuclear forces remain survivable, communicable, and politically usable. However, if NC3 systems are degraded or disrupted, that assumption weakens. Deterrence begins to erode not because nuclear weapons are absent, but because their employment becomes uncertain or delayed. In such a scenario, adversaries may calculate that they can act with greater freedom at the conventional level, confident that escalation can be managed or avoided. 

Policy Recommendations

This evolving threat environment demands a recalibration of Australia’s defense and deterrence posture. Nuclear deterrence remains essential, but it is no longer sufficient on its own. It must be reinforced by a comprehensive strategy that integrates conventional resilience, grey-zone competition, and a more explicit recognition of the role nuclear forces play in underpinning deterrence across all domains.

First, Australia should prioritize the hardening and resilience of NC3-related infrastructure on its territory. This includes enhancing physical protection, investing in redundancy and dispersal, and strengthening cyber defenses. Facilities such as Pine Gap and Harold E. Holt must be able to operate under contested conditions, ensuring continuity of communication and decision-making even in the face of sustained disruption. This may also require the development of alternative communication pathways, including space-based and mobile systems. Resilience is not merely a defensive measure; it is a core component of deterrence, signaling to adversaries that attempts at degradation will not succeed.

Second, Australia must significantly expand its undersea surveillance and anti-submarine warfare (ASW) capabilities. The ability to detect, track, and, if necessary, neutralize hostile submarines in Australia’s maritime approaches is critical to protecting strategic infrastructure. Investments should focus on integrated undersea sensor networks, maritime patrol aircraft, autonomous systems, and closer operational integration with allies. A persistent and credible ASW posture will complicate adversary planning, increase operational risk, and reduce the feasibility of covert operations targeting NC3 nodes.

Third, Canberra should deepen strategic dialogue with Washington on the role of Australia within U.S. nuclear deterrence architecture. This dialogue must move beyond general assurances and address specific contingencies, including how attacks on NC3 infrastructure in Australia would be interpreted. Greater clarity around escalation thresholds, attribution challenges, and response options will reduce the risk of miscalculation and strengthen the credibility of extended deterrence. This should include regularized nuclear consultation mechanisms and scenario-based planning.

Fourth, Australia should take the lead in advocating for the development of an Indo-Pacific nuclear alliance. Such a framework that brings together the United States, Japan, South Korea, the Philippines, Papua New Guinea, and Australia, would formalize shared deterrence responsibilities and strengthen collective resolve. While politically sensitive, this arrangement could include elements of nuclear consultation, planning, and burden-sharing, similar in principle to NATO’s nuclear sharing arrangements. By distributing deterrence functions and signaling unity, such an alliance would complicate adversary calculations and reinforce the credibility of nuclear deterrence across the region.

Fifth, Australia must engage India more directly on the implications of Russian strategic behavior. As a key regional power with longstanding ties to Moscow, India occupies a unique diplomatic position. Canberra should clearly communicate its concerns regarding Russian military activities in the Indo-Pacific, including the risks posed to critical infrastructure and regional stability. In parallel, India should be encouraged to consider the broader consequences of a hypothetical Russian attack on Australia, not only for bilateral relations, but for its strategic partnerships with both the United States and Australia. This dialogue would not seek to force alignment, but to underscore the interconnected nature of regional security and the potential costs of strategic ambiguity.

Sixth, Australia should explore options to visibly anchor U.S. nuclear deterrence in the region. This necessitates a proactive approach to alliance integration. Mechanisms such as enhanced consultation, increased transparency around nuclear policy, and potential participation in nuclear planning arrangements could reinforce deterrence by demonstrating resolve and cohesion. Initiatives under AUKUS provide a foundation for this deeper integration and should be expanded to include broader deterrence considerations.

Seventh, Australian defense policy must explicitly recognize the interdependence of conventional and nuclear deterrence. Investments in long-range strike, cyber capabilities, and undersea warfare are essential, but they must be understood as part of a broader deterrence framework. These capabilities contribute to resilience and denial, but they are ultimately underpinned by the threat of escalation. Ensuring that this relationship is clearly articulated in strategy and doctrine will strengthen deterrence coherence and improve signaling to adversaries.

Finally, Australia must broaden its strategic focus to account for multiple nuclear-capable adversaries operating in the Indo-Pacific. While China remains the primary focus of defense planning, Russia’s increased presence in Southeast Asia underscores the need for a comprehensive approach. Strategic competition is no longer confined to a single actor or domain. It is multi-faceted, simultaneous, and increasingly coordinated. Australia’s deterrence posture must reflect this complexity.

Conclusion

The central lesson is clear. Deterrence in the 21st century cannot be treated as a layered system in which nuclear weapons sit passively at the top. Instead, nuclear deterrence must actively underpin and reinforce every level of conflict, including the conventional and grey-zone domains. Adversaries are increasingly seeking to exploit gaps between these layers, using conventional means to achieve strategic effects without triggering nuclear retaliation.

To respond to this challenge, Australia must take seriously the credibility of the nuclear deterrent on which it relies. This means investing in the resilience of critical systems, strengthening conventional capabilities, and engaging more deeply with allies and partners on the role of nuclear alliances and forces in regional security.

In an era defined by ambiguity and threshold management, the effectiveness of deterrence will depend on integration, clarity, and resolve. By advancing new nuclear alliance structures, deepening strategic dialogue, which includes India, and reinforcing both conventional and nuclear pillars of deterrence, Australia can ensure that sophisticated conventional threats do not undermine the stability of the broader strategic order.

Natalie Treloar is the Australian Company Director of Alpha-India Consultancy, a Senior Fellow at the Indo-Pacific Studies Center (IPSC), a Senior Analyst at the National Institute for Deterrence Studies (NIDS), and a member of the Open Nuclear Network. Views expressed are the author’s own.

Silent Signals: Russian and Chinese Conventional Threats to NC3 and U.S. Extended Deterrence in Australia was originally published on Global Security Review.

These domains and areas are being weaponized for strategic purposes, as adversaries target cross-domain North Atlantic Treaty Organization (NATO) interests with the intent of weakening the Western security architecture and fragmenting alliance cohesion. The Trump administration must work closely with NATO allies to confront the many challenges that face them.

Strategic challenges, such as the Arctic, deep sea, and space, and the threats they pose require improved joint military readiness, enhanced deterrence by denial capabilities, and improved intelligence, surveillance, and reconnaissance.

“Over the last 15 years,” writes Scott Savits, “the Arctic has become a renewed theatre of military competition…. [T]op Russian officials have referred to the Arctic as Russia’s ‘Mecca,’ and a large fraction of Russia’s economy is based on Arctic fossil fuels and minerals.” Frustrating Russian efforts to gain a strategic advantage in the Arctic is of paramount importance to NATO’s deterrence mission.

Russia gaining an advantage in the Arctic will enhance its ability to establish escalation dominance against NATO in the event of a conflict with the alliance. Deterring Russia from broadening the scope of conflict, by threatening NATO’s vital interests in the Arctic, remains critical in dissuading other adversaries, such as China, from seeking to gain similar advantage.

With China developing and deploying new detection technologies in anti-submarine warfare, American nuclear submarine capabilities are becoming increasingly vulnerable to detection and targeting. China’s “Death Star” satellite claims to possess detection capabilities that renders the ocean transparent for up to 500 meters beneath the surface, putting American submarines at risk.

In the space domain, it is estimated that loss of access to space would come at a cost of roughly One billion pounds per day to the British economy. The reported deployment of Russian anti-satellite weapons systems (ASAT) in space are clearly coercive moves designed to threaten NATO’s space assets.

Russia’s weaponization of space is especially concerning as NATO depends on space to conduct an array of operations across the spectrum of deterrence and defence. Most notably, NATO airpower relies on space-based and space-dependent systems to fulfil a series of critical security functions. Leveraging robust deterrence capabilities in orbit, through targeting Russian and Chinese space-based military and non-military assets, is critical to securing NATO’s vital interests in space.

Beyond seeking strategic advantage, China is also expanding and modernising its nuclear arsenal at an unprecedented rate since the end of the Cold War. The Pentagon forecasts that China will be a nuclear peer of the United States by 2035. The latest figures published by the Federation of American Scientists show that China now possesses at least 500 operationally deployed nuclear weapons—up 43 percent from 2020.

Russian President Vladimir Putin continues to undermine international norms by persisting in threats to use battlefield nuclear weapons in Ukraine. Russia also deploys dual-use satellite technologies in space, capable of carrying nuclear warheads into orbit, in direct contravention of long-standing international treaties such as the Outer Space Treaty (1967), which prohibits the weaponization and nuclearization of space.

Meanwhile, Iran, a latent nuclear state, coerces the West by threatening the weaponization of its nuclear program. Iran also infiltrated the West by creating extremist networks through community centers, laundering money in major European and American cities that is used by criminal gangs to plot and execute terrorist attacks.

Proxies supported by Iran, such as Hamas and Hezbollah, can also launch increasingly devastating attacks. Furthermore, attacks like October 7, 2024, or September 11, 2001, do not warrant nuclear retaliation. A nuclear response to a terrorist attack, depending on the attack, is likely a disproportionate response.

China and Russia also engage in subversive activities within the cyber domain, sowing discord by using disinformation, intellectual property theft, and malign interference to destabilize NATO member states. Cyberattacks on critical national infrastructure can also inflict severe levels of damage. The appropriateness of cross-domain responses is yet to be decided.

The cyber attacks against Estonia in 2007, which lasted for 22 days, did not result in the triggering of NATO’s Article 5 collective defense clause. Yet, it was an attack on a NATO member state. The character of the attack complicated the process by which a viable and appropriate retaliatory response could be devised. In a multidomain threat landscape, hostile state actors conducting their operations in the grey zone can claim plausible deniability.

China, Iran, Russia, and North Korea also hold joint exercises, share intelligence, exchange military capabilities, and share a diplomatic and political kinship. This axis of Western adversaries shares the same geopolitical and economic objectives. They seek to replace the international rules-based order and establish alternative institutional frameworks to global order that undermine concepts such as democracy, human rights, rule of law, and national sovereignty.

Militarily, nowhere is this more apparent than in Russia, where Iranian drones and North Korean soldiers were provided to aid Putin’s war in Ukraine. Politically, emerging international blocs such as the BRICS demonstrate the extent to which countries like China and Russia are gaining traction in driving alternatives to the current order.

“As hybrid threats evolve to encompass the whole of digital and networked societies,” wrote Sean Monaghan, “so too will the capabilities required to deter them. A more complex threat environment will make predicting attacks and vulnerabilities more difficult, so nations may rely more on resilience.”

Hence, for deterrence to be effective today, credibility must incorporate more than hard power capabilities. Red lines must be communicated effectively across different channels. Resolve must be demonstrated through a force posture that includes a willingness to establish escalation dominance in a crisis scenario. The art of deterrence is also about determining and holding at risk what an adversary values.

As the outgoing US Secretary of Defence General (Ret.) Lloyd Austin said in 2022, cross-domain deterrence “is the right mix of technology, operational concepts, and capabilities—all woven together and networked in a way that is credible, flexible and so formidable that it will give any adversary pause…. [It is] multidomain, spans numerous geographic areas of responsibility, is united with allies and partners, and is fortified by all instruments of national power.”

Ultimately, deterrence is about credibly threatening to impose unacceptable costs, by denial or punishment, on a would-be aggressor. Those costs must convince the would-be aggressor that they outweigh any potential gains made.

Therefore, it is imperative for the US and NATO to increase cross-domain capabilities to match those of adversaries. Adopting a combination of different violent and non-violent means, to conduct deterrence credibly across multiple domains and at various levels of intensity, will enhance NATO’s ability to secure its vital interests in an increasingly volatile era of global strategic competition.

Alex Alfirraz Scheers holds a diploma in Politics and History from the Open University, a bachelor’s degree in War Studies and History from King’s College London, and a master’s degree in National Security Studies from King’s College London. He has held research positions at the Henry Jackson Society and the International Centre for the Study of Radicalisation, and his articles have been published in the Diplomat, Times of Israel, RealClearDefense, and the Royal United Services Institute. Views expressed in this article are the author’s own. 

Deterrence and NATO’s Emerging Security Environment was originally published on Global Security Review.

This week’s EAR Report brings critical updates on global security dynamics in a world fraught with geopolitical tensions and nuclear threats. ​ From the evolving nuclear doctrines of major powers to the strategic imperatives of missile defense, we provide a comprehensive overview of the current state of international security. ​ Understanding these developments is crucial for policymakers and the public as nations grapple with the complexities of deterrence and defense. ​

Strategic Developments: New Russian Nuclear Doctrine Summary ​

Russian President Vladimir Putin has ratified a revised nuclear doctrine, emphasizing nuclear deterrence against potential adversaries, including countries and military alliances that view Russia as an enemy. ​ The doctrine allows for nuclear responses to significant threats to Russia’s sovereignty, even from conventional weapons, and includes the possibility of nuclear retaliation if Belarus, as part of the Union State, is attacked. ​

Homeland Missile Defense ​

North Korea, Russia, and China continue to enhance their long-range missile capabilities, posing a threat to the U.S. homeland. ​ The next U.S. president must prioritize restoring credible missile defense. ​ Recommendations include developing space-based sensors for persistent missile tracking, advancing boost-phase intercept technologies, and creating a multi-layered defense framework incorporating land, sea, air, and space interceptors. ​ The goal is to counter both rogue state missile salvos and limited nuclear launches from major powers. ​

Deterring the Nuclear Dictators: Foreign Affairs by Madelyn Creedon and Franklin Miller ​

The U.S. faces renewed nuclear threats from Russia, China, and North Korea. ​ The Biden administration has updated nuclear-targeting guidance to deter these adversaries simultaneously. ​ However, modernization efforts for the U.S. nuclear deterrent are hampered by industrial base limitations, material shortages, and funding gaps. ​ The next administration should expedite modernization without extensive policy reviews, focusing on replacing aging systems and enhancing the defense industrial base. ​

Key Takeaways

1. Russian Nuclear Doctrine: Emphasizes deterrence against adversaries and allows nuclear responses to significant threats, including conventional attacks. ​
2. Missile Defense: Urgent need for a comprehensive, layered missile defense system incorporating advanced technologies and space-based sensors. ​
3. U.S. Nuclear Deterrence: Updated guidance to deter multiple adversaries; modernization efforts must be accelerated to address current and future threats. ​
4. Industrial Base Challenges: Modernization of the U.S. nuclear arsenal is hindered by industrial limitations and funding issues. ​
5. Strategic Imperatives: The U.S. must maintain a robust nuclear triad and enhance its defense capabilities to ensure national and allied security. ​

ICBM EAR Report – November 22 was originally published on Global Security Review.