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.
