Policy planning reflected that belief. Governments prepared for escalation management, energy disruption, and post-conflict instability not for sustained deterrence or a prolonged, high intensity war. This failure was neither accidental nor confined to a single capital or political party. It was the result of long-standing policy choices, alliance design decisions, and a shared belief that restraint could substitute for credible deterrence.

A Long Arc of Under-Resourcing

The NATO alliance arrived at this moment after more than a decade of deliberate under-investment. Under Presidents Barack Obama and later Joe Biden, U.S. defense policy emphasized escalation avoidance, fiscal restraint, and risk management over capacity, readiness, and industrial depth. Deterrence became a matter of signaling rather than a consistent force structure.

This trajectory did not change meaningfully during President Donald Trump’s first term. Budgetary turbulence, government shutdowns, continuing resolutions, and inherited top lines constrained structural change. Europe took its cues from Washington as strategic restraint aligned with European politics. Risk aversion, energy accommodation with Russia, and the belief that diplomacy could compensate for declining hard power. This was publicly validated when Obama was awarded the Nobel Peace Prize, not for altering U.S. strategy, but largely for reaffirming a posture Europe favored. The signal was unmistakable: restraint would be rewarded, not penalized.

Alliance Design and the Shock of 2022

NATO functioned exactly as designed. After the Cold War, the United States explicitly asserted its leadership and structured the alliance accordingly. Command arrangements, rank hierarchies, and decision-making processes ensured that Washington always held the most senior voices in the room—and an effective pocket veto.

The shock in 2022 was not that Europe took the lead, but that President Biden was so timid as to reinforce Russian risk assessments. Escalation anxiety, combined with under-resourced deterrence, produced caution when decisiveness was needed. Europe, constrained by years of deferred defense investment and structural energy dependence, lacked both the capacity and the political will to move faster than Washington. The result was paralysis by design: American restraint set the ceiling, European limitations set the floor, and the Western alliance’s action was trapped in between.

Europe Attempts to Lead

European leaders deserve credit for attempting to break the paralysis when the scale of Russian aggression became unmistakable. Boris Johnson effectively accelerated the accession of Finland and Sweden into NATO by signing bilateral security guarantees that would have placed NATO forces on the ground and triggered Article 5 through cascading alliance obligations. It was a brilliant realist move, anchoring deterrence in forward commitment rather than process. Overcoming a Europe constrained by alliance structure, capacity, and the limits of American political cover.

Energy Sovereignty as a Deterrence Variable

A critical and under-appreciated failure was Europe’s abandonment of energy sovereignty. Years of policy choices have left European economies structurally dependent on Russian hydrocarbons at precisely the moment when deterrence required resilience. In 2024, the EU bloc purchased approximately €21.9 billion ($23.5 billion) worth of fossil fuels from Russia—exceeding the €18.7 billion ($20 billion) it reported allocating to Ukraine in financial aid over the same period. Climate change was elevated as the dominant strategic threat, displacing hard-power competitors such as Russia and China in threat prioritization and in efforts to defend Ukraine from Russian invasion. That disordering of risk mattered.

Europe compounded its vulnerability by dismantling reliable nuclear capacity before a dependable replacement baseload was in place. Rather than sequencing decarbonization alongside firm alternatives, several states removed nuclear generation while relying on Russian gas to bridge the gap. This was not a technical error but a strategic one.

Deterrence is weakened by dependence and strengthened when leverage is denied. The destruction of the Nord Stream pipelines did not create Europe’s vulnerability; it exposed and accelerated its resolution. It removed Russia’s most potent instrument of coercive leverage over Europe. The act dismantled a dependency that had distorted European decision-making and narrowed the range of credible responses.

The Burden-Sharing Reality

The deeper problem exposed by the war is not under-spending, but misaligned responsibility. Europe accounts for nearly 44 percent of NATO’s combined GDP yet contributes 32 percent of alliance defense spending and a smaller share of high-end industrial capacity. That disparity was sustainable only so long as American support was unconditional and inexhaustible. It is not.

Fixating on President Trump’s demand for fairness obscures this structural reality. Trump did not create alliance stress; he exposed it. The core issue is that NATO has evolved into a system in which the United States bears disproportionate escalation risk while Europe enjoys disproportionate security benefits. In any conflict in which U.S. and European equities are asymmetric, that imbalance creates credibility problems—and adversaries can see them clearly.

Europe has begun to wake up. Defense budgets are rising, industrial capacity is being rebuilt, and strategic rhetoric has hardened. However, it took Vladimir Putin’s war—his willingness to use force at scale on Europe’s borders—to force a reckoning that European leaders had long postponed.

Interests, Narratives, and Credibility

Deterrence rests on perception of strength and credibility. When responsibility, risk, and capability are asymmetric, resolve is questioned. Credibility erodes quietly, long before it collapses publicly.

The uncomfortable truth is that U.S. and European interests are not perfectly aligned. Europe increasingly speaks the language of realism. Deterrence, balance, and forward defense, while framing policy through a liberal narrative of norms, process, and institutional legitimacy. That mismatch is not illegitimate, but it becomes dangerous when it masks unequal contributions and obscures who bears the true costs of failure.

Necessary Correction

The solution is neither retrenchment nor recrimination. It is a shift toward genuine Regional Shared Deterrence: a model in which European states meet NATO obligations proportionate to their economic weight, rebuild industrial capacity at scale, restore energy sovereignty, and assume visible responsibility for regional defense outcomes. That, in turn, would allow the United States to lead decisively without carrying the alliance alone—restoring credibility through aligned incentives and shared risk.

Ukraine did more than halt a Russian invasion. By refusing to collapse, it shattered Western assumptions and disrupted plans built around convenience rather than genuine deterrence. That disruption has exposed a simple truth: deterrence that is under-resourced by design and shared only in rhetoric will fail when tested. Whether this moment produces a strategic correction—or merely another cycle of improvisation—will determine the next crisis long before it arrives.

Kirk Fansher is a retired Colonel, Senior Fellow at the National Institute for Deterrence Studies, and Editor at Global Security Review. A Yale graduate and U.S. Naval War College alum, he has published extensively on nuclear posture, extended deterrence, and burden sharing. The views expressed are his own.

Ukraine and the Failure of Western Assumptions was originally published on Global Security Review.

The near completion of Iran’s nuclear weapon brings to mind another rogue state’s activities. In 2006, after years of global efforts aimed at preventing the Kim regime from obtaining nuclear weapons, North Korea (DPRK) conducted its first nuclear test. Today, the DPRK has an estimated 50 nuclear weapons and fissile material for 6 or 7 more.

An in-depth comparison of US engagement with Iran and the DPRK’s nuclear programs requires a much longer paper. However, a brief comparative analysis of American deterrence of these adversaries is possible. Applying national interests, objectives, and activities, a methodology employed by decision analysis experts yields interesting results.

Globally, the United States has an enduring interest in safeguarding its national security and sovereignty. Underneath this enduring interest, it has a core objective of defending allies and partners, including through credible deterrence (e.g., preventing conventional and/or nuclear attacks on allies and partners by the DPRK, China, Russia, and Iran). Other major American objectives include safeguarding the free flow of commerce, countering transnational threats, preventing regional domination or aggression, and advancing nonproliferation.

The United States advances deterrence through a range of activities, including the presence of its own military assets and security cooperation with allies and partners. In the Indo-Pacific, this includes mutual defense treaties with Australia, the Philippines; South Korea, and Japan (the latter two of which are explicitly covered by the US nuclear umbrella); arms sales to Taiwan; and military exercises with allies.

More recently, the Trump administration emphasized increased allied defense spending to support “burden-sharing.” Given the limitations of the American industrial base, this is necessary even as the US maintains efforts to prevent Chinese and North Korean aggression.

Deterrence against North Korea is successful insofar as it keeps the North from invading the South or launching nuclear strikes on US Indo-Pacific allies. However, this deterrence is increasingly complicated by Chinese and Russian protection of the DPRK through mutual defense treaties.

This lends greater urgency to the American call for allies to increase defense spending, as there is a real risk of simultaneous conflict with China and North Korea, a scenario requiring substantial military assets in the region. Fulfilling the objective of regional deterrence also requires containing aggression from adversaries and bolstering security cooperation with allies and partners.

The United States supports deterrence in the Middle East by deploying its military forces and cooperating with allies and partners. However, regional deterrence, which does not formally extend the US nuclear umbrella to regional allies and partners (including Israel), often manifests as kinetic operations against adversaries, whether through security assistance or direct attacks. Thus, in the Middle East, deterrence also means advancing the goals of counter proliferation and degrading terror groups who threaten allies.

Unlike in the Indo-Pacific, where the United States prefers to contain aggression and expansion from nuclear-armed adversaries without firing a shot, in the Middle East, it will employ kinetic means to fulfill its objectives. For decades, the United States deterred Iran through sanctions, negotiations, and the threat of military action. It was when President Trump believed Iran’s uranium enrichment program was “at its highest levels and…unprecedented for a state without nuclear weapons” that the US conducted kinetic attack.

The deep rifts in Middle East politics complicates the activities needed to maintain deterrence in the region. Prospects for security cooperation between Israel and the Gulf states, for example, are challenging given the history of the Arab-Israeli conflict, including Israel’s recent strike against Hamas in Qatar.

Deterrence must also account for energy security concerns, given that US attempts to contain a nuclear-armed Iran may lead the regime to weaponize its control over the Straits of Hormuz. It is also unclear how far back American strikes set Iran’s nuclear program. If Iran’s proxy network persists, they can also commit further violence against the United States, its allies, and partners through attacks on military, commercial, and civilian targets.

None of these challenges are simple. In the coming years American deterrence guarantees to allies and partners may look very different as the nation shifts focus to the homeland and the Indo-Pacific. It remains to be seen how this imperative is realized in the forthcoming National Defense Strategy. Some critics note that, in practice, the United States remains heavily focused on the Middle East and Europe. Much of the ability to deter Iran and North Korea will be determined by these larger strategic shifts.

As American decision-makers face questions about effectively deploying American power across the globe, analyzing national interests, objectives, and activities can provide a helpful framework. Assessing the requirements needed to advance larger regional goals brings trade-offs into focus, better preparing the American warfighter for multiple threat scenarios. In short, this approach can yield meaningful results for those in the decision-making chair at critical moments when faced with complex problems, including maintaining credible deterrence.

Nathan Heath is an analyst at NSI. Views expressed are his own.

Deterrence of North Korea and Iran: Interests-Objectives-Analysis Framework was originally published on Global Security Review.

Japan and the Republic of Korea (ROK), as key American allies, should strengthen their conventional military capabilities, both offensive and defensive, to reinforce regional deterrence. Two critical steps are needed. First, Japan and South Korea must expand their capabilities to neutralize North Korea’s missile launchers. Second, Japan’s defense architecture should be aligned with South Korea’s Three-Axis System to create an integrated deterrence framework.

So far, to address concerns over potential nuclear decoupling, the US, Japan, and South Korea have explored multiple options. In addition to Washington’s repeated assurances that its nuclear extended deterrence remains intact, discussions have included modernizing American nuclear weapons, expanding nuclear-sharing agreements, redeploying tactical nuclear weapons to South Korea, and even the possibility of South Korea developing its own nuclear arsenal.

However, South Korea acquiring nuclear weapons remains highly improbable due to its significant political costs. From the 1960s to the 1980s, North Atlantic Treaty Organization (NATO) member-states feared the US might hesitate to retaliate with nuclear weapons if the Soviet Union launched a nuclear strike on Europe. While NATO pursued multiple strategies—most notably the dual-key system and the deployment of Pershing II missiles—these measures never fully resolved nuclear decoupling concerns.

Ultimately, NATO never confronted the full extent of this dilemma as the Soviet Union collapsed in 1991. Since the issue lies not in the US’s ability to retaliate but in its willingness to do so under specific conditions, the most practical approach is to adopt deterrence measures that North Korea perceives as credible.

First, Japan and South Korea should prioritize expanding their capabilities to neutralize North Korea’s nuclear missile launchers. A key advantage for the US, Japan, and South Korea—compared to NATO during the Cold War—is that North Korea is estimated to have around 50 nuclear warheads, far fewer than the tens of thousands in the Soviet arsenal.

In this context, Japan’s planned acquisition of enemy base strike capabilities should focus not only on expanding the number of available strike assets but also on improving their precision and destructive power to ensure maximum effectiveness against North Korean launch sites. At the same time, South Korea’s kill chain should further enhance its deep-strike capabilities by increasing assets like the Hyunmoo-4 missile, which is designed to penetrate deeply buried facilities.

Additionally, South Korea’s Drone Operations Command, established in 2023, should undergo a major expansion in drone assets capable of effectively detecting, tracking, and striking North Korean missile launchers. By integrating high-precision missiles and unmanned systems, both Japan and South Korea can significantly reduce North Korea’s ability to deliver nuclear strikes, thereby reinforcing deterrence.

Second, as Japan and South Korea expand their strike capabilities, Japan’s defense architecture should be aligned with South Korea’s Three-Axis System. This integration would allow both countries to allocate their finite military assets more effectively when targeting North Korea’s nuclear-related ground units. For example, given the geographic distance, Japan could focus on striking fixed targets such as command centers and underground missile storage sites while South Korea concentrates on eliminating mobile launchers that require rapid response and precision strikes.

Additionally, harmonizing Japan and South Korea’s missile defense structures would improve the likelihood of intercepting North Korean missiles. While Japan has developed its missile defense in close coordination with the United States, South Korea has opted to develop its own independent missile defense system, instead of fully integrating into the American-led ballistic missile defense framework.

However, aligning the two countries’ missile defense systems would significantly enhance regional interception capabilities. A fully integrated defense network would not only establish a more layered interception system against incoming North Korean missiles but also enable earlier response times—as Japan and South Korea deepen their real-time missile-tracking cooperation—South Korea’s response times could improve further. By improving both offensive and defensive coordination, Japan and South Korea can maximize deterrence and reduce North Korea’s nuclear strike effectiveness.

By implementing these measures, North Korea would be left with only a limited number of launchers capable of delivering nuclear weapons. While it is possible that some missiles could still be launched from the remaining launchers and a few might evade American missile defenses, North Korea would have to consider allocating few nuclear warheads against Japan, South Korea, and the United States. This would be necessary both to achieve its long-term political objectives and to deter US-ROK combined forces and US Forces Japan (USFJ) from retaliating in the short term.

Moreover, North Korean leadership would face significant uncertainty about whether its remaining nuclear missiles could successfully penetrate American missile defenses. In essence, by increasing their conventional strike capabilities and aligning their military strategies, Japan and South Korea could ensure that a substantial number of North Korean launchers are neutralized. This would force Pyongyang to operate with significantly reduced military options, making its attempt to create nuclear decoupling less credible.

However, this strategy is only viable as long as North Korea’s nuclear arsenal remains limited. If Pyongyang dramatically expands its warhead stockpile and launch platforms, conventional deterrence alone will no longer be sufficient, and the risk of nuclear decoupling will escalate beyond control. The US, Japan, and South Korea must act decisively—before the balance of power shifts irreversibly in North Korea’s favor. Time is running out.

Dr. Ju Hyung Kim, CEO of the Security Management Institute, a defense think tank affiliated with the South Korean National Assembly, is currently adapting his doctoral dissertation, “Japan’s Security Contribution to South Korea, 1950 to 2023,” into a book.

Strengthening Nuclear Deterrence in the Far East was originally published on Global Security Review.