South Korea's Autonomous Defense

South Korea Is Building for the Alliance and for Itself 

By Daniel Sneider, lecturer in East Asian studies at Stanford University, non-resident distinguished fellow at the Korea Economic Institute of America, and APP Member. 

First Published July 20, 2026 on the blog of the Korea Economic Institute of America.

The United States and South Korea describe the latter’s defense buildup with the same enthusiasm but mean two different things. American officials call it “alliance modernization,” while South Korean officials increasingly call it “autonomous defense.” Neither side has much incentive to dwell on the difference, but it is getting harder to avoid.

As the Donald Trump administration tells it, South Korea is increasing defense spending and equipment procurement within the context of a redesigned U.S. strategy to restructure the roles of both U.S. and South Korean forces on the Korean Peninsula and beyond.

Modernization is the “administration’s shorthand for pushing U.S. allies to adapt to a changing regional security environment and shoulder more of the defense burden,” Brookings Institution’s Andrew Yeo observed last fall. Writing for the latest edition of KEI’s Korea Policy, Korea National Defense University’s In Hyo Seol described modernization as “a redistribution of roles on a foundation of converging military interests.” 

This framework is a more comfortable one for those concerned about friction between the United States and South Korea. Differences over specific issues, such as the timeline for returning wartime operational control (OPCON) of South Korean armed forces, can be more easily managed if both Washington and Seoul share the same goal of alliance modernization.

Autonomous Defense

But the reality is more complicated. South Koreans increasingly place their defense buildup and its key components within a different, though not entirely contradictory, policy framework called “autonomous defense.”

Autonomous defense traces its roots to the fear of abandonment in the 1970s, when then President Richard Nixon withdrew 20,000 troops from the peninsula during the Vietnam War. More recently, defense autonomy for South Korea means greater self-reliance, indigenous weapons procurement sustained by arms exports, and ultimately limiting the reliance on U.S. forces as a deterrent to North Korea. 

South Korean policymakers have long grappled with a persistent tension in defense policy between a desire for more autonomy and the reality of the operational indispensability of the U.S.-South Korea alliance. “The goal of autonomy policy is to hold our own while being alliance compatible,” a senior South Korean official told the author on a recent visit to Seoul. In other words, South Korea hopes to shift the alliance’s internal balance of power, reduce technological dependency on U.S. defense systems, and build sufficient indigenous capability to make Seoul a more equal partner.

On the surface, the Trump administration’s goals of shifting a greater share of defense burdens to its allies and encouraging a more regional approach to security would seem to be compatible with South Korea’s preferences. But Washington has been clear about the limits: allies are expected to spend more, not to build alternatives.

The OPCON transfer initiative, for example, was initially targeted in 2012 but has since been replaced by a conditions-based threshold with no fixed timeline. The conditions range from South Korea’s own capability, both in equipment and command, to lead combined forces, its strike and air defense capabilities, and most nebulous of all, the existence of a regional security environment that would be compatible with the transfer.

In 2019, the allies determined that South Korea met a minimum baseline capability and interoperability with U.S. Forces Korea (USFK). Further progress slowed until recently, when the Trump and Lee Jae Myung administrations agreed that a second stage, full operational capability, would be verified this year. Seoul seems likely to establish 2028 as a new target year for OPCON transfer to occur by. 

That push has been met, however, with resistance from the U.S. military, led by USFK Commander Xavier Brunson, who suggested earlier this year that this timeline was too optimistic. The U.S. Senate has backed that up by proposing tighter conditions for OPCON transfer. 

Arms Production and Exports

Similar tensions lurk not far below the surface when it comes to South Korea’s indigenous arms production and its successful export drive across Europe and Asia. Sales of armored vehicles, artillery, jet aircraft, and missile defense systems have transformed the country into a global leader of arms sales. Earlier this month, President Lee attended a NATO forum and suggested such weapons sales could underpin an evolution of South Korea-NATO ties. But senior Trump administration officials have seemingly pushed back on the notion that allies could or should replace reliance on American weapons.

“The simple fact of the matter is that no alternative country or countries can compete with the U.S. defense industrial base, either in quantity or quality,” Pentagon policy chief Elbridge Colby asserted on social media last week. The United States “makes the best equipment, and we make it at a scale that no plausible competitor can match,” Colby continued. Access to the U.S. defense industrial base “is a privilege, not a right.”

Thus, even in its most ambitious formulation, South Korea’s autonomous defense still involves maintaining the U.S. extended deterrence commitment in the face of threats from North Korea. Some sort of U.S. military presence makes that political commitment concrete.

“The withdrawal of USFK is not something we want to see,” a senior Lee administration official told this writer. “But if it becomes a reality for us, and we have to fend for ourselves, we need to block the threat of nuclear weapons.”

The most obvious way to do so—and the one that has attracted the most attention in American policy circles—is a South Korean nuclear weapons program. Alternatively, policymakers in Seoul are interrogating whether rapid changes in defense technology might create a reliable form of conventional deterrence. The first option is still beyond the pale, while the second is still a ways down the road.

“We are learning the lessons of the Ukraine and Iran wars,” the senior official explained, notably laser weapons and AI-powered defense systems that can “potentially intercept hundreds of missiles at one time.” 

For now, neither the United States nor South Korea has an interest in forcing the question. But indigenous production, export markets, command authority, and the first sketches of a conventional answer to nuclear coercion add up to more than burden-sharing.

Can South Korea Hedge?

How South Korea Can Buy Alliance Insurance

by Daniel Sneider, lecturer in East Asian studies at Stanford University, non-resident distinguished fellow at the Korea Economic Institute of America, and APP Member. 

First Published April 28, 2026 on The Peninsula.

The case for South Korea hedging its relationship with the United States may be harder to dismiss. Washington’s trade policies and the economic consequences of the U.S.-Israeli war on Iran have raised the cost of close alignment at the same time they have weakened confidence in U.S. commitments. Seoul has options short of rupture, that include joining regional trade frameworks, arming Ukraine directly, and pursuing its own diplomacy with Iran on energy shipments.

“While the biggest threat to the alliance remains North Korea, the biggest challenge to the alliance now comes from the United States,” argues long-time Korea watcher [and APP member] Bruce Klingner. “Having bullied Seoul into a disadvantageous trade deal that violated the U.S.-South Korea free trade agreement and the U.S. Constitution, the Trump administration is demanding more and promising less to its security and economic partners.”

“The U.S. may have degraded military deterrence by undermining the perception – in the minds of both allies and opponents – that Washington is a dependable security partner,” Klingner said.

This sense of unreliability is hardly confined to South Korea—it is felt by all U.S. allies. As Washington Post columnist Fareed Zakaria wrote recently, the United States has used allied security dependence “to squeeze them hard.” The response is not to break ties with the United States “but to accept that our interests are no longer as close as they once were, and that in current circumstances it cannot be a high priority to accommodate American wishes,” writes prominent British historian and commentator Lawrence Freedman.

The result, wrote Zakaria, is that allies “have decided to buy insurance, to protect themselves from an unreliable America.” In that spirit, below are three ideas for South Korea to develop an insurance policy against U.S. uncertainty.

Accelerate Application to Join CPTPP

The most urgent—and, in some ways, easiest—step toward greater independence for South Korea is to expedite its application to join the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP). The twelve-member economic and trade pact is the kernel of an alternative free trade system, particularly if it partners with the European Union, which is under discussion. It offers a comprehensive framework for addressing not only traditional trade markets but also supply chain cooperation, digital trade, and state-owned enterprises.

There are several advantages for South Korea in joining CPTPP. “The Iran war, rising protectionism and a deepening divide between the United States and China have reshaped the international economic order,” Asan Institute for Policy Studies President Choi Kang wrote in Joongang Ilbo. “For Korea, a mid-sized trading nation, survival now depends on diversifying markets and stabilizing supply chains. The CPTPP offers a network well suited to those goals.”

Aside from market gains, CPTPP membership would also cement the strategic partnership between South Korea and Japan, as well as with other partners who share similar issues with the United States, such as Australia, Canada, and the United Kingdom.

South Korean membership in CPTPP has been under discussion for some time. “Earlier this decade, Japan had given South Korea its very cold shoulder on entry,” Michael Beeman, former Assistant U.S. Trade Representative for Japan, Korea and APEC [and APP member], told this writer. “Kishida-era warming in Japan-ROK ties seemed to have turned that around.”

The recent joint statement following the meeting between South Korean President Lee Jae Myung and Japanese Prime Minister Sanae Takaichi indicated Japanese support for South Korea’s membership. “I don’t sense Japan’s posture is any longer a top obstacle,” says Beeman, author of Walking Out, an authoritative book on U.S. trade policy.

The greater obstacle seems to stem from South Korean domestic politics, driven by fears among agricultural producers and auto manufacturers that CPTPP membership will lead to greater competition from Japanese and other foreign producers. But supporters argue that structural adjustment assistance for vulnerable sectors could mitigate those effects and that the CPTPP could catalyze much-needed restructuring of South Korean industries.

Lift Restrictions on Arms Sales to Ukraine

A more controversial step would be for South Korea to lift long-standing restrictions on the sale of lethal weapons to countries engaged in active combat, and in particular to Ukraine. South Korea has provided indirect weapons support by selling weapons to allied states such as Poland and non-lethal systems to Ukraine, as well as other forms of aid and participation in NATO mechanisms to finance U.S. weapons to Ukraine. But there is an urgent need to intensify support for Ukraine, particularly in areas such as missile defense systems, because of the Trump administration’s decision to cut U.S. military assistance to Ukraine and divert weapons to the Iran war.

Changing South Korea’s policy on arming Ukraine would signal its readiness to take positions that differ from those of the United States and would immensely strengthen its ties with the European Union. Rather than acting on behalf of the United States, as some South Korean progressives argue, this would demonstrate South Korean independence of action and self-defense.

By bolstering Ukraine’s defense, South Korea would also strengthen its own security interests by preventing a Russian victory that would only drive North Korea and Russia closer together. Morally and strategically, it would balance the impact of North Korea’s participation in the Ukraine war.

An Independent Approach to Iran and Maritime Security

The Lee administration has taken initial, though still tentative, steps toward shaping an independent policy response to the U.S.-Israeli war against Iran and maritime security in the Strait of Hormuz. But there are grounds to argue that South Korea, perhaps in tandem with Japan, should negotiate directly with the Iranian regime to seek exemptions for the passage of its stranded vessels.

One important initiative underway is President Lee’s decision to participate in the European-led multilateral mission to secure the free passage of ships through the strait once the war is over. Lee attended the recent international summit led by France and the United Kingdom and stated that South Korea was ready to make “substantive contributions” to this mission, including using South Korean military forces to clear mines and escort passage following a stable ceasefire.

If the Islamabad talks fail, the alternative may be a “broad based international coalition” that strikes a deal with Iran, wrote British strategist Freedman.

Given the uncertain outcome of the war and the collapse of even the pretense of direct talks, Seoul should accelerate its own diplomacy toward Tehran. Earlier this week, South Korean special envoy Chung Byung-ha traveled to Iran to meet with Iranian Minister of Foreign Affairs Abbas Araghchi to request cooperation on the safe transit of all vessels, particularly Korean ships, through the Strait of Hormuz.

Conclusion

So far, however, Seoul has decided not to pay the toll fee requested by Tehran for ship passage. It may be time, however, to reconsider that decision, though it is likely to anger the Trump administration. The most effective approach would be to coordinate with Japan, which not only shares South Korea’s extreme dependence on Middle Eastern oil and gas but also maintains its independent ties and diplomacy with Iran.

None of these steps is without cost. But the pressures driving them are unlikely to ease over the next three years, and the question for Seoul is not whether to create distance from Washington but how much, and on what terms.

Burning a lot of bridges

Redrawing America’s Security Bargains in Northeast Asia

by Daniel Sneider, lecturer in East Asian studies at Stanford University, non-resident distinguished fellow at the Korea Economic Institute of America, and APP Member. 

First Published February 11, 2026 on the Peninsula Blog of the Korea Economic Institute.

The stability of Northeast Asia has long rested on two strategic bargains with South Korea and Japan, forged out of the Korean War and formalized in security treaties. South Korea was compelled to accept the de facto division of the country in exchange for a treaty commitment, manifested in continuous U.S. ground forces, to defend against any North Korean threat of attack. With Japan, the bargain was different. The security pact provided a broad U.S. security umbrella, allowing Japan to focus on its economic recovery. In exchange, Japan provided bases and infrastructure that allowed U.S. air, naval, and marine infantry forces to project power regionally and globally. Both bargains depended on extended deterrence, or the credible threat that the United States would use force, including nuclear weapons if necessary, to protect its allies. That commitment also reduced incentives for South Korea and Japan to develop their own nuclear arsenals.

U.S. National Security and Defense Strategies
Donald Trump’s White House believes in a very different version of these security bargains. This was laid out in two documents—the National Security Strategy (NSS), issued in late November, and the National Defense Strategy (NDS), issued in late January.

Taken collectively, the Trump administration’s policymakers envision a situation in Northeast Asia and the Western Pacific where South Korea has the principal, if not almost sole, responsibility for defense against a potential North Korean attack. U.S. forces are repurposed and perhaps redeployed with a regional mission, mainly aimed at China, with potential use in situations such as a Taiwan contingency. Both South Korea and Japan are pushed, in turn, to not only spend much more but also to focus their spending on building capacities to defend the First Island Chain rather than their own territories.

As this writer noted in an earlier commentary, the NSS contained no mention of the U.S. defense of Korea and Japan, nor of extended deterrence commitments. Instead, Washington says it “must urge these countries to increase defense spending, with a focus on the capabilities—including new capabilities—necessary to deter adversaries and protect the First Island Chain.”

Strikingly, the NSS did not reference the Korean Peninsula broadly and did not reaffirm the long-standing goal of North Korean denuclearization. There was also no mention of the new strategic alliance between North Korea and Russia, despite Russia’s potential to vastly improve North Korea’s weapons of mass destruction program. The document also dilutes the potential China threat, focusing primarily on economic terms.

The NDS largely follows that framework but offers at least some limited discussion of the security environment in Northeast Asia and the Western Pacific. China’s military buildup is less of a direct threat in the NDS’s language than a rising power that needs to be balanced by the United States and its allies. The goal is one of an offshore counterweight, one more appropriate to the reduced global role envisioned by the Trump administration. The document also acknowledges that North Korea poses “a direct military threat” to South Korea and Japan and that the former must stay vigilant against the threat of invasion. While there is a nod to North Korea’s nuclear capability, there is no mention of the role of the nearly 30,000 U.S. forces stationed in South Korea.

Instead, the NDS states South Korea “is capable of taking primary responsibility for deterring North Korea with critical but more limited U.S. support.” What that support may be is not spelled out, but both the NSS and NDS hint that this may include the removal of U.S. ground and air forces, or at least their redeployment elsewhere. “This shift in the balance of responsibility is consistent with America’s interest in updating U.S. force posture on the Korean Peninsula,” according to the NDS. Extended deterrence is totally absent, or even the clear commitment made in the security treaty to fully defend South Korea.

The Colby Speech
Under Secretary of Defense for Policy Elbridge Colby presented the implications of these policy statements more explicitly during recent visits to South Korea and Japan in late January. Colby stated the central purpose of U.S. national security policy in the Western Pacific as the search for a “stable balance of power” with China. To that end, Colby told an audience of elite Korean policymakers:

“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 the region.

Colby praised South Korea’s defense spending, calling the country a “model ally.” But in what may be considered a stunning omission for any senior U.S. defense official visiting Seoul, there was not a single word devoted to North Korea, its nuclear and missile buildup, its military axis with Moscow, or the United States’ seventy-three-year-long commitment to defend against it.

This was not lost on the audience. “In an 18-minute address, Colby mentioned China seven times but did not refer to North Korea even once,” the major daily Chosun Ilbo wrote in its account. Colby, whom the South Korean media credited as leading the drafting of the NDS, which was issued just before his arrival, “made these points during meetings with senior South Korean government officials.”

The Pursuit of a Trump-Kim Summit
The White House directed Colby to omit North Korea from his public comments as part of an effort to convince North Korean leader Kim Jong Un to meet President Trump again, a source within the administration told this writer on condition of anonymity. Talk of a meeting, perhaps tied to Trump’s planned visit to China in April, has been widely circulating. “The White House is opening a line of communication to Kim,” the source said.

“Considering how the Trump administration has sent mixed signals on this from day one, it is not really that surprising,” says Clint Work, a Research Fellow at the National Defense University. “I read it similarly, as an effort to tamp down language so as to try and open an avenue to, at the very least, talk with Pyongyang,” Work told the author.

South Korean officials offered little in the way of public reaction to Colby’s message. One reason for this is that President Trump threatened higher tariffs on South Korea the same day that the message was delivered, ostensibly because the National Assembly is slow-walking approval of a trade deal made last year. The timing was so coincidental that it sparked speculation that the tariff move was meant to reinforce Colby’s defense message, but sources within the Trump administration deny that intent.

For its part, the Lee Jae Myung administration may see a U.S. retreat serving its own goals of greater defense autonomy and engagement with North Korea. The South Korean president recently called on the country to rid itself of a “submissive mentality” of being dependent on others. A less engaged United States may accelerate the timetable for South Korean forces to assume operational control on the peninsula, create space for South Korea to enrich nuclear fuel, and incentivize new kinds of defense partnerships, such as in nuclear submarine technology. Support for nuclear armament remains high across South Korea as well.

South Korean policymakers have long resisted the idea that U.S. forces in the country should have any role other than defending against North Korea, or be reduced. But there is more willingness, says Work, to acknowledge and grapple with the idea that U.S. forces may need the “strategic flexibility” to deploy outside the peninsula.

South Korea-based researchers articulated the long-standing counterpoints to such flexibility in a recent paper published at one of the nation’s foremost think tanks, the Asan Institute for Policy Studies. “South Korean administrations have resisted any changes to U.S. force posture on the Korean Peninsula, whether in terms of total size or operational focus,” argue Peter Lee and Esther Dunay. “This is due to the ongoing North Korean military and nuclear threat, fears of a potential entanglement in any Taiwan Strait conflict, and longstanding fears of alliance abandonment.”

On the surface, the U.S. alliances with South Korea and Japan remain intact and manageable. But beneath that appearance of solidarity, the Trump administration’s attempts to redraw the security bargains that have underlain stability and peace in Northeast Asia are creating growing tension and uncertainty.

“We’re burning a lot of bridges,” the administration source told this writer. “We’re stressing the relationships with our allies.”