Remarks by Under Secretary of War for Policy Elbridge Colby at the Sejong Institute in South Korea (As Delivered)

Thank you for that kind introduction, Dr. Kim, thank you Ambassador Lee, and thank you to the Sejong Institute for hosting me here today. It's a distinct personal honor. The Institute has earned a sterling reputation for convening serious discussions on the issues that most directly shape regional and global security. So it is a personal privilege and honor to be here, and it is a personal privilege and honor to be here in South Korea on my first international trip as Under Secretary of War for Policy. And it is a privilege to address you today to give a sense of our thinking at the Department of War and across the administration.

We are living through a time of genuine strategic transition. For much of the post-Cold War period, American defense policy was shaped by abstractions, assumptions of permanent unipolarity, and ambitions that were untethered from geopolitical reality. Strategy became unmoored, and drifted away from concrete matters of power, geography, and limits. The result was neither stability nor the end of history, but rather frustration and squandering of resources, credibility, and public trust.

President Trump was elected in large part to reverse that sorry course. From the outset, he rejected vague promises and unfocused commitments in favor of a hard-nosed assessment of American interests and the realities of power. Under his leadership, as the 2025 National Security Strategy makes so clear so well, the United States has returned to an approach to strategy grounded in what the NSS (National Security Strategy) calls flexible realism: clarity about priorities, discipline about commitments, resolve about follow-through, and seriousness about deterrence.

The United States is greatly fortunate to be in an era of tremendous economic revival under President Trump's leadership. At the same time, as the National Security Strategy and the newly-released National Defense Strategy lay out, the Indo-Pacific is now a primary center of gravity of global growth, a hub of global manufacturing, including here in South Korea, and the geopolitical hinge of the 21st-century. As a result, as these documents make clear, Americans' long-term security, prosperity, and liberties will be decisively shaped by developments in this region.

With stakes of this magnitude, clarity matters. Americans need to be clear-eyed about what our interests are in Asia, what we are prepared to do to defend those interests, and what a satisfactory equilibrium looks like. A satisfactory stability in Asia will not be gained and preserved by lofty rhetoric, putative norms, or ostensibly good intentions. It will not be guaranteed by economic interdependence or diplomatic symbolism. Rather, it will be preserved by power intelligently and rightly applied-and specifically by a durable favorable balance of power that, as the National Security Strategy lays out, prevents domination of this crucial region by any single state.

This is the logic behind President Trump's long-standing emphasis on peace through strength that is so clearly reflected in the Department of War's 2026 National Defense Strategy. This is not about needless confrontation. This is not about forever wars. It is instead about the protection of American and allied interests through a stability rooted in credible deterrence and strategic balance.

Achieving this, though, is easier said than done. It thus requires being clear-eyed about both our goals and the means to achieve them.

To that end, President Trump has been clear that we can and should strive for a stable, peaceful relationship with China that protects the interests of the United States and our allies. The United States under President Trump's wise leadership does not seek to dominate China, nor do we seek to strangle or humiliate it. What we seek-and what the President has consistently articulated-is a genuinely stable equilibrium that works for Americans as well as for our allies: a favorable balance of power in which no state can impose its hegemony. This stability will allow us to trade with each other and for our nations to prosper, agreeing where we can and differing where we must in a respectful and clear-eyed fashion. As Secretary Hegseth laid out in his important 2025 Shangri-La remarks, that is the practical approach we are pursuing - and one, he stressed, that works not only for Americans but for peoples throughout the region striving for further economic growth and their sovereign independence in charting their national futures. And that is the foundation of a decent peace.

At the same time, as Secretary Hegseth has also made clear, including most recently in December in his landmark remarks at the Reagan National Defense Forum, we must be clear-eyed about China's ongoing military modernization and buildup, and the growing activities of its military in this region and increasingly beyond. I say that not as an accusation but rather as a simple but evident observation-a material fact with which we must engage seriously.

Yet we can and will address this not with a posture of needless confrontation but rather one of focused, deliberate strength and reasonable clarity about our goals and the means needed to achieve them. As the secretary says, strong and clear, but quiet. We are not pursuing regime change against Beijing nor seeking to dominate China. We acknowledge and respect China's proud history.

Instead, as the secretary elucidated last month and the National Defense Strategy makes clear, our defense strategy in the Indo-Pacific centers on deterrence by denial along the first island chain. Guided by the President's direction in the National Security and National Defense Strategies, we are focused on building a military posture in the Western Pacific that ensures that aggression along the first island chain is infeasible, that escalation unattractive, and war is indeed irrational. This includes a resilient, distributed, and modernized force posture across Japan, the Philippines, the Korean Peninsula, and elsewhere in the region, a posture optimized for a denial of quick or decisive gains through military force, that is resilient rather than fragile, and that binds us together in our shared pursuit of peace and stability.

This approach is motivated by just that - the desire for peace and stability. But it is rooted in the age-old dictum that deterrence is strongest not when threats are loud but not backed up, but rather when outcomes are predictably favorable and credibly communicated. It is, in other words, a military strategy matched to a geopolitical strategy of positive realism.

In the same spirit, we are simultaneously carrying the olive branch, as the National Defense Strategy puts it. As President Trump has rightly emphasized, strength and diplomacy must work together, and thus a stable balance of power is reinforced by communication, transparency, and risk reduction. That is why the Department will continue to pursue respectful, professional communication with China-focused on strategic stability, crisis management, and reducing the risk of miscalculation and miscommunication.

The Secretary and I have already engaged with Chinese counterparts with respect and openness but also confident strength and clarity; we and other Department leaders will continue to do so. We are not naïve about what these interactions can achieve. Yet we also recognize their value not only in clearly conveying and receiving messages, but in demonstrating respect.

This is powered by the clarity of our motivation: We are not seeking a hostile relationship with Beijing. We are seeking a stable one: a decent peace.

Even as stability cannot be built on hope, however, neither can it be unevenly distributed in who bears the responsibility for ensuring it. Such a stability of a decent peace needs to be undergirded by deterrence, and thus must be underwritten by hard power capability, capacity, and will-ours, to be sure, but also that of our allies.

Here too President Trump has shown the way, being candid about a reality many leaders skirted for a generation: that, for too long, the security of key regions rested disproportionately on American resolve and contributions while many allies underinvested in their own defense. That imbalance is neither fair nor sustainable. It does not make sense for regular Americans - the people who voted President Trump into office. Nor though does it make sense for our allies, who were encouraged to rely too much on an unsustainable model that unreasonably overweighted burdens on regular Americans.

Redressing this requires recognizing a clear reality: A favorable balance of power requires capable allies with real military strength, real industrial capacity, and real political resolve. President Trump has consistently argued that alliances are strongest when they are based on shared responsibility rather than permanent dependency. The model he has laid out is based on simple common sense: Alliances are most durable and formidable when they are partnerships. With each member motivated by love for its own country, when the alliances are grounded in shared interests, and when they governed by pragmatic mutual respect and adaptation.

President Trump has already demonstrated the superior results of this model in short order. Not only for Americans, but for our allies. For a generation, polite American pleas to Europeans to spend more on defense fell on deaf ears. Rather, Europeans effectively calculated that they could continue to underspend and America would, motivated by gauzy abstractions like the "rules-based international order," still hold the bag as we say in the U.S. The upshot of that was the result in the dramatic weakening of European military power - something that benefited neither Europe nor America, and was a violation of the noble example of the Cold War, when Europe did pull its weight far more.

Now, thanks to President Trump's leadership, our NATO allies - after decades of underinvestment - have pledged to meet what the National Security Strategy and National Defense Strategy declare as a new global standard of allied defense spending: 3.5% of GDP on core military functions.

But, I must stress, these principles apply as much in Asia as they do in Europe.

Now this is intimately and fully understood and reflected in action here in this great country of South Korea. And that is why my first international trip as Under Secretary of War for Policy is to the Republic of Korea.

South Korea understands strategic reality. It of course does not have the luxury of abstraction on war from reality. South Korea has invested consistently in its own defense because it understands geography, threat, and the centrality of concrete military power. And in this time, President Lee's decision to increase defense spending to 3.5% to this new global standard and to assume greater responsibility for South Korea's conventional defense reflects a clear-eyed and sage understanding of how to address the security environment that we all face, and how to put our storied and historic alliance on sound footing for the long haul.

That is a rational, practical, and hard-headed response to step up to partnership. It is in America's interest to be sure, but even more, it is in South Korea's interest. And that is exactly the kind of action and logic that the United States is encouraging from our allies.

And precisely how to ensure that our alliances are put on the strongest footing for the long term.

That is why we are so optimistic about our alliance with South Korea, a model ally. Our alliance with the Republic of Korea is adapting because the world is evolving. Such adaptation, such cleared-eyed realism about the situation that we face and the need for greater balance in the sharing of burdens will ensure that deterrence remains credible, sustainable, and resilient in this changing world. This is, again, common sense. Strong partnerships, strong alliances like the alliance between the United States and South Korea do of course rest on shared history and values.

And of course we marked last year, the outbreak of the Korean War, that we fought so memorably together, our people. And we will mark the 75^th anniversary of the alliance in a few years. And it is, of course, essential to mark and honor that shared history.

But at the end of the day, alliances cannot be built on sentiment alone. They must rest on aligned interests, shared risk, proportionate contributions, and mutual benefit.

So let me close with a simple observation. When there is a favorable balance of power, peace is possible. When it collapses, conflict becomes much more likely. Peace is a product of focused strength and preparation, not a state of affairs that can be taken for granted.

President Trump has restored this common sense but, before his Presidency, far too heterodox approach to statecraft in the United States. That peace is preserved not simply by abstractions, but by marshaling strength in equitable and sustainable ways. Not by ostensibly noble aspirations, but by grappling wisely with the fundamentals of power. Not by slogans, but by discipline and realistic strategy.

In this vein, the goal of American defense policy in Asia should be clear and reasonable to all. It is not confrontation with China or anyone else, for that matter. The goal is rather, a reasonable equilibrium that works for Americans, for our allies, and indeed for the whole region. It is an adaptive and emergent, not formalistic, hidebound regional order. One defined by a favorable balance not hegemony, in which sovereignty is respected, and in which peace is sustained-not by comforting illusions, but by clarity, strength, and resolve.

This is the logic of peace through strength. This is the logic of deterrence by denial. This is the logic of our strategy.

And this ultimately is the foundation of a decent and durable peace in the Indo-Pacific-one that will benefit not only Americans but also people throughout this vital region.

Thank you very much.