NATO’s recent establishment of Baltic Sentry (2025), Eastern Sentry (2025), and Arctic Sentry (2026) reflects more than a response to Russian aggression. Collectively, these operations demonstrate how modern deterrence has evolved to address persistent airspace violations, hybrid warfare, cyber-attacks, sabotage of critical infrastructure, and grey-zone coercion. While these missions are conventional military operations, they derive their strategic credibility from something far more significant, NATO’s integrated nuclear deterrence architecture.

This distinction is critical. NATO’s Sentry operations are not isolated military activities; they are conducted within an alliance whose conventional forces are underwritten by the collective nuclear capabilities of the United States, the United Kingdom, and France. Any adversary contemplating escalation understands that conventional confrontation with NATO carries the inherent risk of nuclear escalation. This integration between conventional and nuclear deterrence has underpinned Euro-Atlantic security for more than seventy years.

For the Indo-Pacific, the lesson is clear. As China rapidly expands its nuclear arsenal, North Korea continues to develop increasingly sophisticated nuclear and missile capabilities, and Russia under Vladimir Putin has revived Cold War-era nuclear coercion, regional allies cannot assume that conventional military cooperation alone will provide credible deterrence. If deterrence is to succeed, it must be built upon a coherent nuclear alliance before a crisis emerges, not after deterrence has already failed.

Conventional Operations Backed by Nuclear Deterrence

The strategic significance of NATO’s Sentry operations lies not simply in what they do, but in what stands behind them. Baltic Sentry enhances surveillance and protection of undersea communications cables, energy infrastructure, and maritime approaches following repeated acts of sabotage and suspicious activity in the Baltic Sea. Eastern Sentry reinforces NATO’s eastern flank through enhanced air policing, intelligence sharing, and rapid response capabilities in the face of persistent Russian military activity. Arctic Sentry reflects NATO’s growing focus on the High North as Russia and China expand their military presence in an increasingly contested region.

These operations improve situational awareness, interoperability, and alliance readiness. Yet none of them exist in isolation. Their credibility stems from NATO’s integrated command structure, collective defense commitments under Article 5 of the North Atlantic Treaty, shared military planning, and, fundamentally, the Alliance’s nuclear deterrence posture. NATO’s Nuclear Planning Group, alongside the independent nuclear forces of the United Kingdom and France and the United States extended nuclear deterrence commitments, ensures that any conventional confrontation carries strategic consequences far beyond the immediate theater.

This layered approach to deterrence is central to NATO’s success. Conventional operations deter day-to-day coercion, while nuclear deterrence prevents adversaries from believing they can escalate a conventional conflict without unacceptable consequences. The two cannot be separated; together they create a coherent deterrence architecture.

The Indo-Pacific’s Strategic Environment Has Changed

The Indo-Pacific now faces a security environment increasingly defined by nuclear competition. China’s rapid expansion and modernization of its nuclear arsenal is reshaping the regional balance of power. At the same time, Beijing continues to employ sustained grey-zone coercion through military pressure around Taiwan, coercive operations in the South China Sea, cyber campaigns, and increasingly frequent air and maritime incursions directed at neighboring states.

North Korea’s advancing nuclear weapons and ballistic missile programs add another layer of strategic complexity. Pyongyang’s continued weapons development increases the likelihood that any regional crisis could involve nuclear coercion or escalation.

Meanwhile, Russia’s full-scale invasion of Ukraine has demonstrated that nuclear weapons remain central to great-power competition. Throughout the conflict, President Vladimir Putin has repeatedly employed nuclear rhetoric and strategic signaling to deter Western intervention. The assumption that the end of the Cold War marked the end of nuclear coercion has proven false.

For Indo-Pacific allies, this means they are confronting not one, but three nuclear-armed challengers whose strategic interests increasingly overlap. Yet the region’s security architecture remains fragmented.

The Missing Foundation

The United States maintains strong bilateral alliances with Australia, Japan, South Korea, and the Philippines. Regional initiatives such as AUKUS and the Quad have strengthened defense cooperation, technological collaboration, and strategic coordination. These arrangements make important contributions to regional security.

However, they do not constitute an integrated alliance comparable to NATO. They lack common command arrangements, formalized collective defense obligations across the region, institutionalized nuclear consultation mechanisms, and a unified framework for integrating conventional and nuclear deterrence. This matters because conventional military cooperation alone cannot provide fully credible deterrence against nuclear-armed adversaries. NATO’s experience demonstrates that conventional operations derive their strategic weight from the knowledge that they are backed by a credible and integrated nuclear alliance. Without that strategic foundation, conventional activities risk being viewed as isolated demonstrations of resolve rather than components of a comprehensive deterrence posture. The Indo-Pacific is therefore attempting to strengthen conventional deterrence without first establishing the alliance architecture that gives such deterrence its greatest credibility.

Building Deterrence Before Crisis

History consistently demonstrates that alliances formed during conflict rarely prevent that conflict. They manage its consequences instead. Europe’s recent experience illustrates this lesson. Many of NATO’s most significant reforms, including enhanced forward deployments,

strengthened infrastructure protection, expanded readiness, and the establishment of the Sentry operations, were accelerated in response to deteriorating security conditions following Russia’s aggression against Ukraine. They represent adaptation after strategic warning signs became impossible to ignore.

The Indo-Pacific still has an opportunity to act before reaching a comparable point. Rather than waiting for a crisis over Taiwan, the South China Sea, or the Korean Peninsula to force hurried institutional change, regional democracies should begin developing the alliance structures necessary to sustain credible deterrence.

Such an alliance would not require every member to possess nuclear weapons. Instead, it would integrate conventional planning with extended nuclear deterrence, establish mechanisms for strategic consultation, coordinate contingency planning, strengthen interoperability, and ensure that regional conventional operations are supported by a credible nuclear deterrent capable of deterring nuclear-armed adversaries.

Conclusion

NATO’s Baltic Sentry, Eastern Sentry, and Arctic Sentry operations are not simply conventional military initiatives. They are visible expressions of a much deeper strategic reality: conventional deterrence is most credible when backed by an integrated nuclear alliance. Their effectiveness rests not only on ships, aircraft, and surveillance systems, but on the certainty that any attempt to escalate against NATO would confront the Alliance’s collective nuclear deterrent.

The Indo-Pacific faces an increasingly dangerous strategic environment characterized by a rapidly expanding Chinese nuclear arsenal, an emboldened North Korea, and a resurgent Russia that has returned nuclear coercion to the center of international politics. In such an environment, conventional cooperation alone is unlikely to provide sufficient deterrence.

The central lesson from NATO’s Sentry operations is therefore not that the Indo-Pacific should simply replicate these missions. It is that such operations derive their credibility from the nuclear alliance that stands behind them. Waiting to build that alliance until deterrence has failed would repeat the strategic mistakes history has repeatedly exposed. The time to establish an integrated Indo-Pacific nuclear alliance is before a crisis begins, not after conflict has already become unavoidable.

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

NATO’s Sentry Operations Show Why the Indo-Pacific Needs a Nuclear Alliance was originally published on Global Security Review.

The return of great power competition is especially concerning in the Indo-Pacific, with the expansion of Chinese military capabilities eroding the status quo of a regional rules-based order. An evolution in Chinese strategic objectives has created a shift among American defense planners and strategists, who now see China as the primary adversary of the United States. As written within the 2022 U.S. National Defense Strategy, “The [People’s Republic of China] PRC remains our most consequential strategic competitor for the coming decades… this conclusion [is based] on the PRC’s increasingly coercive actions to reshape the Indo-Pacific region and the international system to fit its authoritarian preferences, alongside a keen awareness of the PRC’s clearly stated intentions and the rapid modernization and expansion of its military.”

In the Cold War, Western strategists and planners spent most of their intellectual capital examining the challenges posed by the Soviet Union, in particular, the deterrence challenges posed by the Soviet nuclear arsenal. Policymakers subsequently developed defensive strategies and associated concepts including extended deterrence and force posturing in Europe and the role that the American industrial, economic, and military could play. Not least among these considerations was the role of U.S. extended deterrence commitments to its allies in NATO, particularly those allies on the front lines of the Cold War stand-off in Europe.

Put simply, extended deterrence refers to the stated policy to defend a foreign ally, including the use of nuclear weapons in said defense, as part of a mutual defense treaty. Many policies supported the credibility of U.S. extended deterrence commitments in Europe, to include public statements by American presidents, the presence of American military personnel abroad, and U.S. nuclear weapons forward deployed in Europe. Extended nuclear deterrence, along with the forward deployment of vast amounts of conventional power, was a central element of America’s defense of its European allies. One of the factors that strengthened the conventional defensive posture of Europe is that Europe enjoys a certain amount of strategic depth.

Strategic depth is defined as the space available within a territory to halt an adversary attack, execute a counterattack, and end the conflict on terms acceptable to the counterattacking party. During the Cold War, NATO enjoyed a regional depth which allowed not only for NATO forces to fall back to more defendable geographic features in the face of a conventional attack, such as the Rhine, the Rhone, or even the Pyrenees, but strategic depth within Europe allowed either side to carry out strikes on European soil without escalating or expanding the conflict to a nuclear war on each other’s homelands.

While this geography served U.S. and allied interests in the Cold War, the United States lacks a similar level of strategic depth in the Indo-Pacific as it confronts the prospects of a large-scale conflict with China. Much of the geography in a U.S.-China conflict would take place over the open ocean and skies of the Western Pacific. As such, there are few defendable terrain features such as rivers or mountain ranges behind which an actor can rest, reset, and prepare for a counterattack.

Just as importantly, a battlefield in the Western Pacific means that there are fewer options for the distribution of basing. American and allied bases would therefore have to generate combat operations from a limited number of high priority bases in a conflict. The lack of defensible features and small number of high-value bases is in many ways the opposite condition of what the United States and its NATO allies experienced in the Cold War.

In contrast, China has enormous strategic depth due to its ability to generate combat power from any number of bases, launch sites, or ports along its enormous Pacific coast and its deep hinterland. In the Western Pacific, U.S. allies and partners are dispersed and in some cases thousands of miles away from each other, with neutral and non-aligned states dotted in between. As a result of the United States’ limited number of bases, owing to the scarcity of permanent land features in the Western Pacific, China can focus on a small number of critical targets to diminish American and allied combat effectiveness.

Further, the limited number of in theater bases increases the demands and stress on an aerial fleet and the logistics involved in keeping U.S. forces adequately supplied. It also makes for significantly longer ship and submarine transit times to and from more distant resupply points. Already in 2015 there was the issue of the rate at which missiles can be launched.

To counter China, the number and availability of sensor resources that can be devoted to integrated air and missile defense systems versus other missions must increase given the vertical proliferation of such systems. Also, the capacity of combat logistics forces needed to cycle ammunition ships between rear bases and forward reloading areas, maintain long-range, high-capacity carrier-based aerial refueling, and to sustain different operational concepts over prolonged periods of conflict must be expanded.

The United States, Japan, and Australia should consider pre-positioning substantial amounts of military capabilities directly relevant to deterrence operations, such as missile defense capabilities, fuel, and conventional munitions, in each other’s territories to create targeting dilemmas for China. Doing so would not only enhance knowledge of deterrence methods and challenges between allies in theater that are vastly different from Western Europe during the Cold War but also create existential misery for PRC defense planners.

Regardless of personal preference, complex issues related to nuclear strategy are now central in the Indo-Pacific region. The U.S. and its allies must deliberately evaluate the profound responsibilities that come with being members of a nuclear alliance.

Robert Peters is a Senior Research Fellow for Strategic Deterrence in The Heritage Foundation’s Allison Center for National Security. Prior to joining Heritage, Peters served as the lead strategist at the Defense Threat Reduction Agency, where he oversaw the office that developed the Agency’s five-year strategy, conducted the Agency’s research and tabletop exercise program, and executed Agency-level program evaluations. Dr. Christine Leah is a Fellow at the US National Institute for Deterrence Studies and has worked on nuclear issues at Yale, MIT, and RAND and in London, Singapore, and Canberra. She is the author of The Consequences of American Nuclear Disarmament and Australia and the Bomb. Views expressed by the author’s are their own.

Extended Deterrence and Strategic Depth was originally published on Global Security Review.

Many assumed it was indeed the end of history. After all, between 1987–1993, Washington and Moscow signed four notable arms control deals: the Intermediate-Range Nuclear Forces Treaty (INF), the Strategic Arms Reduction Treaties I and II (START), the Treaty on the Prohibition of Nuclear Weapons in Outer Space, and the Conventional Forces Europe (CFE) treaty.

Russian strategic nuclear weapons were scheduled to drop from over 10,000 deployed to 3,500 by the year 2000. The INF treaty banned shorter range missiles altogether. And Warsaw Pact conventional forces in central Europe and Russia dropped precipitously.

President Reagan’s economic war against Moscow was successful. It ended the Soviet empire by pushing Moscow to the brink of insolvency. Russia could not financially maintain its formidable Cold War nuclear and conventional force levels.

From 1993–2001, the US did not enjoy the promised “end of history.” State sponsors of terror in Iran, Libya, Afghanistan, and Iraq took the fight to the US, albeit in a different mode than threatening to send massive tank armies through the Fulda Gap into Western Europe.

The US responded with a war that would last more than a decade and cost Americans an estimated $7 trillion. It was all for naught and accomplished very little.

Readiness and Modernization Shortfalls

While spending trillions on nation-building in Iraq and Afghanistan, the US Department of Defense (DoD) suffered from severe readiness and modernization shortfalls. The defense budget was roughly $305 billion in 1991 when the Soviet Union collapsed and almost exactly that in 2001 before 9/11. In the interim the budget dropped to as low as $250 billion and it was only after 1996 that the budget gradually increased to $300 billion.

When adjusted for inflation (1991–2011), the defense budget of $300 billion (1991), aside from “overseas contingency operations,” should have grown to $480 billion by 2011, assuming a 3 percent growth rate. That did not happen. The shortfall in defense spending reached $1.25 trillion during the two decades following the Soviet Union’s collapse.

The base defense budget in 2011 was roughly $500 billion, and at first glance equal to that expected. Out of a defense budget of $656 billion, $160 billion was allocated for the wars in Afghanistan and Iraq. In the two decades from 2001–2021, the Department of Defense spent $1.56 trillion on nation building—an average of $80 billion annually.

Over three decades after the Cold War’s end, the US did not invest in the modernization of the military. The three-decade peace dividend, which saw $2.8 trillion fewer defense dollars spent, was instead spent domestically and on nation building. As a result, the modernization and recapitalization of the armed forces, especially nuclear forces, were postponed.

By September 11, 2001, the US nuclear forces were already in the field for two decades (Ohio-class submarines), three decades (Minuteman III), and five decades (B-52). The nuclear budget, $77 billion at the end of the Cold War, dropped to less about $25 billion, with most of those funds simply maintaining legacy nuclear forces.

It was not until 2009–2010 that the Obama administration and Congress agreed on a plan for upgrading and replacing nuclear forces—three decades after President Ronald Reagan rolled out his nuclear modernization and sustainment plans in late 1981. New systems are projected to begin fielding in 2031 with completion by 2050.

The failure to prioritize the planning and implementation for replacing aging systems included nuclear command-and-control systems, warheads, and all three legs of the nuclear triad. The belief that the world was safer was a fool’s errand.

By shifting federal dollars from defense to social spending, the US also ensured the workforce needed to build nuclear weapons, space and missile defenses, and cyber systems are no longer there. Vendors associated with the building of Ohio-class submarines and the Minuteman III intercontinental ballistic missiles (ICBM) numbered in the hundreds once. Now, the nation is starting from scratch. The submarine industry lost 14,000 workers and now lacks the manpower to meet demand.

As for ICBMs, with the shutdown of the Peacekeeper production line, the US Air Force was left with a guidance and propulsion replacement program that over a period of more than a decade invested $8 billion in making sure the Minuteman III (1970) would stay in the force “through 2030.” Again, many hundreds of vendors no longer exist to make ICBM parts. Even worse is the current state of the available workforce. American universities grant more PhDs in the hard sciences to Chinese students than to American students. Across the board, the US has fewer workers in the hard sciences than needed, although industry is now reaching into the schools to bring students along a planned program of education that leads them to careers in the aerospace business.

The Challenge Ahead

The nation now finds itself in a precarious position at a time when China and Russia are at their most aggressive. The Columbia-class submarine, which will replace the Ohio-class submarine, was recently delayed two years, further increasing costs. And the herculean task of building 450 new ICBM silos armed with 400 missiles will prove costly. The US will maintain the current 400 ICBMs while simultaneously deploying 400 new missiles in new silos. The Sentinel ICBM, a technological marvel, is progressing toward production. It is a highly capable weapon that is planned for initial deployment in 2033.

Chairmen of the Senate Armed Services Committee, Roger Wicker (R–MS) recently concluded, “It will take several years of sustained investment and real growth beyond this down payment to keep pace with China’s military advances…. But to be clear: The cost of deterring war will always be dwarfed by the cost of fighting one.” This could not be more true. It is time the American people understand the challenge facing the nation and what it will take to overcome it.

Peter Huessy is a Senior Fellow at the National Institute for Deterrence Studies. Views expressed are his own.

What Has Been the Impact on Our Nation? was originally published on Global Security Review.

The existing US-led hub-and-spoke alliance system in the Asia-Pacific is fundamentally different than the North Atlantic Treaty Organization (NATO). In the 1950s the US investigated the possibility of establishing a regional multilateral alliance, but this soon proved infeasible. Unable to forge a Northeast Asian equivalent to NATO at the onset of the Cold War, the US opted instead for the “hub-and-spoke” architecture, where the spokes radiate out from Washington in a network of asymmetrical ties reinforcing American regional dominance. Why?

First, compared to Europe, the Asia-Pacific has very little history of multilateral institutions and alliance formation. Modern European states have a history of doing so dating back well before the Treaty of Westphalia was established in 1648. European sovereign political systems emerged out of Westphalia; Europe came to develop different notions of international community and international order, based, in part, on the concept of international law. Asia did not have such a tradition of legalistic international agreements.

Second, geography also plays a significant role in the nature of warfare, and therefore the ability of countries to come to one another’s aid. European nations border each other, but they do so in a land context. As such, not only is it easier to move around troops and military equipment, but it is faster.

The nature of geography and distance also inform countries’ threat perceptions. NATO continues to endure because of a shared common adversary—Russia. Countries neighbor each other, making for an easily delineated bloc. The distances between Southeast Asia and Northeast Asia are formidable compared to Europe. Moreover, the sheer size of China, and the formidable military power of Japan, made it harder for smaller competitors to balance against them.

There were some attempts at bridging East and West. In 1954, the Southeast Asia Treaty Organisation (SEATO) was established because of the Southeast Asia Collective Defence Treaty. It included Australia, France, New Zealand, Pakistan, the Philippines, Thailand, the United Kingdom, and the US and was designed to curb the spread of communism in Asia. A major reason SEATO failed and was disbanded in 1977 was because there was a lack of a common threat perception.

What did survive was the U.S. hub-and-spoke system: the US-Japan alliance as a means of curbing any potential regional Japanese aggression after World War II, the US- South Korea alliance to protect South Korea from a North Korean invasion, and the US alliance with Australia and New Zealand (ANZUS) to protect both nations from perceived threats of communist invasion by China and Indonesia.

Central and critical to the credibility of any alliance system is how it deters conflict. This is arguably much harder to achieve in a multilateral alliance than in the current hub-and-spoke system. Conventional deterrence in the Asian maritime theater is difficult. The most significant work on conventional deterrence was done by John Mearsheimer. However, Mearsheimer’s analysis may be persuasive for eras preceding the development of nuclear weapons, but the pre-nuclear era did not involve missiles. His analysis was based on a European land context, not an Asian maritime context. As such, thinking on conventional deterrence is incomplete.

There are significant logistical challenges that come with trying to establish a multilateral alliance system in Asia. Tasks include the need to ensure the prompt replenishment of destroyed combat ships, establish defensive perimeters for fleet support, and ensure the safety of fleet replenishment oilers and dry cargo/ammunition supply ships, just to name a few.

Budget constraints brought on by sequestration (2013), coupled with longer-term financial uncertainty, was raising questions about the US Navy’s Military Sealift Command and its combat logistics force more than a decade ago. Europe was, and remains, one single geostrategic entity connected by an excellent road network. In the Asia-Pacific, Australia, Japan, South Korea, and Taiwan are more dispersed, with neutral and non-aligned states between them, not to mention a growing Chinese submarine fleet.

American forces need to move around large numbers of ships, aircraft, troops, and munitions. Unless the US establishes more permanent bases on allied territory, it is not clear that the US is able to adequately deploy replacement capabilities on very short notice, especially once conflict breaks out. Whilst American declaratory policy that requires a defense of allies in Asia is sound, it needs to be backed up by raw capability, the two components of deterrence.

For more than a decade, analysts have encouraged the US to improve readiness and sustainment of the US Navy. In 2014, the Center for Strategic and Budgetary Assessments warned of many more similar issues, including how quickly cruisers and destroyers exhaust their missiles and how adversaries will attempt to use “cheap” missiles (such as the BrahMos cruise missile) to attack US warships to get them to use their most effective defenses first,  such as the long-range SM-6 missile, and then strike with more effective weapons to destroy carriers and their escorts.

The foundation of power projection was and remains sea control. As Hugh White argues, what has contributed to making the US such a decisive power in the region is a robust sea-control capacity with low risk, and therefore little cost. The modern concept of sea control has its origins in the writings of Rear Admiral Alfred Thayer Mahan. Sea control was about naval superiority, the concentration of forces, and decisive battles.

Sea control is the condition in which one has freedom of action in specified areas and for specified periods of time and, where necessary, to deny or limit its use to the enemy. Sea control is different from sea denial. The latter refers to attempts to deny an adversary’s ability to use the sea without necessarily seeking to control the sea. When it comes to Asia, China and the United States are gradually trading places when it comes to sea control.

Discussions about a multilateral alliance would arguably have to address the unavoidable question of nuclear weapons and extended nuclear deterrence (END). Discussions within NATO’s Nuclear Planning Group during the Cold War about targeting and basing helped calm nervous allies, helped hold NATO together, and, in some cases, helped stem the tide of proliferation.

Both the US–Republic of Korea Extended Deterrence Policy Committee (EDPC) and the US–Japan Extended Deterrence Dialogue were established after the 2010 Nuclear Posture Review for a similar purpose. There were growing concerns around the ability of the US to overcome China’s anti-access/area-denial capabilities and American support in the event of specific contingencies involving the disputed Senkaku/Diaoyu Islands in the East China Sea. Could these bilateral dialogues become multilateral fora? This applies just as much to conventional weapons, but where the members of the alliance are far apart from each other, the potential red lines of escalation and conflict are much less identifiable than they would be in a land context.

But the technical challenges in the credibility of American extended deterrence to Australia, Japan, and South Korea matter less than the reasons why the US would want to do nuclear strategy again, this time in East Asia, a vastly more complicated theater. What matters is interest.

Hugh White raised the uncomfortable but critical issue when he suggested that Tokyo’s desire for a closer defense relationship with Australia is all about lining Australia up to support Japan against China, and that is the way Washington and Beijing will see it, too. Tokyo and Washington believe that Australia should defend the US-led international order and refuse concessions to China’s ambitions. Australians have not decided whether they agree with the US and Japan and are predisposed to seek a compromise with China—all while retaining a strong American role.

As White argued, no possible US nuclear posture, even the best possible, would eliminate the risk that a conflict with a nuclear-armed great power like China might lead to direct nuclear attacks on US territory. This leaves America’s East Asian allies to ponder whether American interests in the Western Pacific are strong enough for Washington to justify running the risk of conflict going nuclear.

Professor Paul Bracken of Yale University expressed concerns about American alliances in Asia. He found it nearly inconceivable that the US would actually use nuclear weapons to defend Australia, Japan, or Taiwan. Bracken noted that he played out countless scenarios, and that when it came down to it, American leaders were unwilling to use nuclear weapons. Bracken went so far as to suggest that the United States may not engage in a conventional hi-tech war with China, either.

Ely Ratner’s article is thought-provoking, valuable, and timely. But there are significant challenges in alliance credibility in Asia, because interests do not align as easily as they do in Europe. As former US Secretary of State John Foster Dulles remarked in 1952, “The North Atlantic Treaty reflected a sense of common destiny as between the peoples of the west, which grew out of a community of race, religion, and political institutions, before it was finalised. But that element does not clearly exist as yet anywhere in the Pacific area.” The same is true today, seven decades later.

Christine Leah, PhD, is a fellow at the National Institute for Deterrence Studies.  

American Alliances in East Asia: An Australian Perspective was originally published on Global Security Review.

The Implications of a Nuclear Armed South Korea with Lieutenant General In-Bum Chun (ROK, Ret) was originally published on Global Security Review.

The article emphasizes that a U.S. withdrawal of conventional forces from Europe, intended to prioritize the China threat, would be counterproductive. It argues that maintaining a strong U.S. conventional presence in Europe is crucial for effective deterrence against Russia, maintaining NATO cohesion, and ultimately supporting U.S. efforts in competing with China. The author contends that relying solely on nuclear deterrence in Europe would undermine credibility and could lead to a scenario that diverts resources away from Asia.

The team debates the actual impact that potential troop reductions in Europe might have compared to America’s pivot to Asia, amid financial constraints affecting defense spending and the necessity for prioritization in military strategy and accountability in political decisions.

What’s America’s Priority, Europe or Asia? was originally published on Global Security Review.

While certification is contingent on the US Navy’s ability to maintain its own submarine production rate, which is struggling to meet the planned two Virginia-class submarines per year, Australia would benefit greatly from their acquisition. Overall, it is worth noting that AUKUS Pillar I and Pillar II are likely to significantly enhance US undersea capabilities in the long term. Pillar I includes the rotational presence of one UK Astute-class submarine and up to four US Virginia-class submarines at HMAS Stirling, Western Australia, from 2027. HMAS Stirling provides the United States with greater access for the forward presence of nuclear-powered submarines in the Indo-Pacific.

Indo-Pacific access is further expanded via the new submarine base that is planned for the east coast of Australia by 2043. The authorized consolidated Commonwealth-owned Defence Precinct at Western Australia’s Henderson shipyard will provide contingency-docking and depot-level maintenance for AUKUS submarines by 2033, potentially alleviating some of the burden on US-based maintenance facilities. Pillar II will provide the advanced technology necessary to enhance US, UK, and Australian undersea capabilities, particularly for longer term advantages in mobility, survivability, lethality, and sustainability of allied forces.

Conversely, the SLCM-N is likely a significant factor in retaining American undersea capabilities. The SLCM-N will provide the US with flexible deterrence options in austere Euro-Atlantic and Indo-Pacific theatres, particularly as the US needs to provide extended nuclear deterrence to 32 NATO allies plus Australia, Japan, and South Korea. There are three options to consider when attempting to deter China, North Korea, and Russia.

First, the United States can provide Australia three to five conventionally armed Virginia-class submarines. This option is likely to significantly degrade American undersea capabilities through a lack of flexible response options for strategic deterrence and extended nuclear deterrence. Plus, Australia will need to manage three classes of submarines: the Collins-class, the AUKUS-class, and the SSN-AUKUS under this option.

Second, Australia can field a dual-capable submarines (DCS) mission for Australian Virginia-class submarines. This option requires the establishment of a nuclear planning group (NPG) to plan for a DCS mission for Australian Virginia-class submarines. These submarines would be capable of carrying the SLCM-N. This nuclear-armed option is unlikely to degrade US undersea capabilities, as Australia could support some US missions in the Indo-Pacific and provide flexible deterrence options. Australia will still need to manage three submarine classes under this option.

Third, the United States does not sell Virginia-class submarines to Australia, but instead bases submarines armed with SLCM-N in Australia, either on a permanent or rotational basis. This option does not degrade US undersea capabilities. However, under this option Australia should negotiate for extended nuclear deterrence guarantees. This option is not the end of AUKUS, but Australia will need to build sovereign SSN-AUKUS submarines to fill the gap left by Australia’s aging Collins-class submarines when they are retired.

Policymakers should not be afraid to consider a flexible nuclear-armed option in light of recent and historic Russian and Chinese rhetoric on AUKUS, especially when this rhetoric concerns “non-nuclear long-range precision strike capability.” Having a nuclear-armed option would provide enough flexibility to backstop and limit conventional war.

On April 18, 2025, Russia’s envoy to Indonesia, Sergei Tolchenov, defended military ties with Jakarta and did not deny claims that Russia seeks to station long-range military aircraft at the Manuhua Air Force Base at Biak Numfor, about 1400 kilometers north of Darwin, Australia. Russia asserted that AUKUS is more of a threat to the Asia-Pacific than Russian ties with Indonesia, which are “not aimed against any third countries and poses no threat to security in the Asia-Pacific region.” Tolchenov added that challenges to regional stability

are more likely to arise from the rotational deployment of large military contingents from extra-regional states on Australian territory, including the provision of airfields for the landing of strategic bombers and port infrastructure for visits by nuclear-powered submarines. Particularly alarming are the currently discussed plans to deploy the US intermediate-range missiles in Australia, which would put ASEAN [Association of Southeast Asian Nations] countries, including Indonesia, within its range, as well as the acquisition by the Royal Australian Navy of nuclear-powered submarines under the AUKUS trilateral partnership.

These comments are consistent with Putin’s rhetoric against the North Atlantic Treaty Organization (NATO).

This is not the first time Russia and China accused the US, UK, and Australia of risking an intensified arms race and military confrontation in the Indo-Pacific. A report by the China Arms Control and Disarmament Association, China Nuclear Strategic Planning Research Institute, and the Russian Energy and Security Research Centre stated, “non-nuclear long-range precision strike capability, being provided to Australia, will affect nuclear deterrence and strategic stability.” The report goes on to say that “[w]hile current non-nuclear strategic weapons cannot carry out all the missions assigned to nuclear weapons those still can produce strategic effects.” The report further criticizes AUKUS’ nuclear submarine cooperation, which the report suggests will trigger a regional submarine arms race.

Chinese and Russian threats should not limit or contain AUKUS to non-nuclear options. This is particularly true when the US has historically provided non-nuclear long-range precision-strike capability. In the past this included the F-111 Aardvark, F/A-18F Super Hornet, E/A-18G Growler, and F-35A Lightning II.

Under the UN Charter, members have “the inherent right of individual or collective self-defence if an armed attack occurs.” Hence, Australia and its allies should stand by the expression, si vis pacem, para bellum. Australia and its AUKUS allies should not back down from non-nuclear long-range precision strike capability or nuclear-armed deterrence options that provide more flexible responses.

Although, the sale of Virginia-class submarines to Australia under the AUKUS agreement may be contingent on the US Navy’s ability to maintain its submarine production rate. It is worth noting that American undersea capabilities, particularly in the long term, may be greatly enhanced through other means under AUKUS Pillar I and Pillar II.

In the new era of nuclear disorder, the key to maintaining American undersea capabilities will likely be the SLCM-N deployed on Virginia-class attack submarines. The SLCM-N will provide AUKUS flexible deterrence options and limit risk of conflict in austere Euro-Atlantic and Indo-Pacific theatres.

Natalie A. Treloar is a Senior Analyst at the National Institute for Deterrence Studies. She is the Australian Company Director of Alpha–India Consultancy. Natalie formerly contracted to the Australian Department of Defence. Views expressed in this article are solely those of the author and do not necessarily reflect the views, policies, or positions of any organization, employer, or affiliated group.

SLCM-N, the Virginia-Class Submarine, and AUKUS was originally published on Global Security Review.

The international system is now firmly bipolar, with China’s global power rapidly increasing at a time when Russia regularly threatens to use nuclear weapons against the North Atlantic Treaty Organization (NATO), influencing the administration of President Donald Trump. The combined Chinese and Russian threats are leading President Trump to warn of a possible World War III.

American power is increasingly contested, bringing new operational challenges to extended deterrence. A fundamental question is now in play—should the US abandon the Nuclear Non-Proliferation Treaty (NPT) it created in 1960s and instead push its allies to field nuclear weapons?

Allies are already reconsidering their nuclear stance. In the Asia-Pacific, American ally Australia provides useful historical insights.

From the late 1940s to the early 1970s, Australia sought to acquire nuclear weapons in response to an unstable international order where it felt threatened by China. In 1967, Secretary of US Defense Robert McNamara said it would be “entirely natural” and “an obvious thing to happen” for Australia to acquire nuclear weapons in response to China developing them. He also expressed interest in establishing a collective nuclear organization for the Far East, “starting with Australia and the Philippines.”

Indeed, Secretary of State Dean Rusk earlier suggested a “US-supplied Far Eastern nuclear stockpile” open to Japan and India. In 1958, others proposed the US could base intercontinental ballistic missiles (ICBMs) in Australia, in the event the US decided to keep tight control of nuclear weapons in its own hands and actively worked to push its allies to agree to the NPT treaty.

There were similar debates around friendly nuclear proliferation in Europe around the same time. Aiming to regain leadership in Europe, the US proposed a multilateral nuclear force within NATO. While there were doubts over its military utility, the diplomatic discussions that started around sharing nuclear hardware and control did allow time to develop a European non-proliferation solution. In 1966, the NATO nuclear planning group was established, allowing some European allies to be involved in how and under which circumstances American weapons might be used.

The structural changes in the international system that prompted these earlier ideas are happening again. It is time to start thinking seriously about the next steps to take. The nuclear history noted suggests three broad approaches.

First, allies might build their own nuclear forces. The logic is that in a high-intensity conflict between the US and a nuclear power, the adversary may target American allies with nuclear weapons. Such an escalation demonstrates an adversary’s willingness to coerce allies into ceasing support for the United States.

This is the worst-case scenario that extended deterrence was created to prevent. If allies seriously doubt American credibility, fielding independent nuclear forces is a solution.  Indeed, economically challenged Pakistan and North Korea took this path already. For America’s allies, acquiring nuclear forces may be a lower cost option than growing their conventional forces.

Second, allies might work together to devise a modern multilateral nuclear force as considered in 1960s Europe. In the Pacific, Australia considered working with Britain on nuclear weapons in the late 1940s and 1950s; some still favor this effort. In that regard, Japan and Australia have recently acquired Tomahawk cruise missiles, which the US armed with nuclear warheads to deter Russia in the 1980s. Such weapons might be a starting point for an allied nuclear force in the eastern Pacific. As noted, the US considered deploying ICBMs in the Australian outback.

Third, another option, arguably better for American global leadership, is to address the allies’ deepening concerns over extended deterrence. This would involve the current administration actively reassuring allies that it still places importance on existing security treaties, increasing nuclear sharing and including more nations in nuclear planning, especially in the Pacific. Such steps would be at marginal cost to the US.

The most important might be nuclear sharing as this appears a tangible example of commitment. Of course, nuclear sharing is actually a misnomer since the US shares in the employment of certain nuclear weapons. It retains full control of the weapons prior to an authorization to strike a target.

The US could increase nuclear sharing with Pacific allies, such as Australia, Japan, and South Korea, and broaden out to other NATO nations like Poland and the Scandinavian nations, which appear to be Russia’s next target after Ukraine. These nations could then reciprocate in hosting US nuclear weapons as Belgium, Germany, Italy, and the Netherlands do now.

This discussion hinges on American ambitions for global leadership. As the Trump administration pushes allies to bare a greater share of their own security while attempting to close a $2 trillion annual deficit, the US must necessarily cut costs everywhere. Thus, American allies must take a realistic look at what President Trump is seeking to accomplish with the federal budget and understand that they must step into the breach while the US sets its house in order.

Sometimes, a great power must admit that it may be in its interests to change direction and push its allies down a new, different path. In that case, the Trump administration might declare the NPT finished and instead encourage its allies to go nuclear.

Dr. Christine Leah is a Fellow at the US National Institute for Deterrence Studies and has worked on nuclear issues at Yale, MIT, and RAND and in London, Singapore, and Canberra. She is the author of The Consequences of American Nuclear Disarmament and Australia and the Bomb. Dr. Peter Layton is Visiting Fellow at the Griffith Asia Institute and an Associate Fellow at the Royal United Services Institute. He is author of Grand Strategy and coauthor of Warfare in the Robotic Age.

Time to Proliferate Nuclear Weapons (or Not?) was originally published on Global Security Review.