The Koreas | Security | East Asia

Trump’s Hormuz Warship Request Puts South Korea-US Alliance to the Test 

President Lee Jae-myung faces a difficult dilemma as he seeks to uphold the South Korea-U.S. alliance while avoiding entanglement in a drawn-out war against Iran.

The South Korea-U.S. alliance is being put to the test again amid U.S. President Donald Trump’s repeated call for South Korea to deploy warships to the Strait of Hormuz. On March 14, Trump urged several countries to send warships to the critical maritime chokepoint in an effort to reopen the blockaded passage. On his Truth Social platform he wrote, “Hopefully China, France, Japan, South Korea, the UK, and others, that are affected by this artificial constraint, will send Ships to the area so that the Hormuz Strait will no longer be a threat by a Nation that has been totally decapitated.” 

Trump’s request for warships has put South Korea and its allies in a strategic dilemma. So far, allied nations have been hesitant to commit warships to the passage and have instead been weighing their options. However, as Trump’s patience grows thin and the pressure of alliance expectations mounts, the window for strategic ambiguity is closing. On March 15, Trump intensified pressure on his allies, warning, “Whether we get support or not, I can say this – and I said it to them: we will remember.”

Dubbed the world’s “energy artery,” the Strait of Hormuz is responsible for the passage of approximately a fifth of the world’s crude oil and a third of liquefied natural gas (LNG). Iran’s blockage of this key maritime passage has pushed oil prices above $100 per barrel, hitting energy-import-dependent countries such as South Korea particularly hard.

Asian countries overall import roughly 60 percent of their oil from the Middle East, with dependence reaching approximately 70 percent for South Korea and 75 percent for Japan. The global energy crisis has posed a significant risk to South Korea’s economy by disrupting its high-tech and manufacturing industries. 

South Korean President Lee Jae-myung faces a difficult dilemma as he seeks to uphold the alliance and reaffirm Seoul’s commitment to Washington amid ongoing trade negotiations, while also maintaining cordial relations with Middle Eastern countries. On one hand, failing to satisfy Washington’s demands could strain the alliance and result in consequences in the form of weaponized interdependence and economic statecraft. 

On the other hand, there is a growing chorus of concerns in Seoul that becoming directly involved in the U.S.-led maritime operation by deploying warships could provoke retaliation from Tehran and jeopardize Korean commercial and industrial interests in the Middle East. Creating unnecessary friction with Iran and becoming militarily embroiled in the Middle East does not align with Lee’s pragmatic diplomatic approach, particularly as $68 billion worth of South Korean corporate projects in the region are already at risk. In fact, several South Korean conglomerates, including Samsung, SK, and Hyundai Motor, currently operate around 140 overseas subsidiaries across the region.

For now, South Korea has adopted a more cautious stance as it assesses the evolving situation, seeking to avoid becoming entrapped in an unwanted conflict with Iran. In response to Trump’s request, a Blue House official stated, “We will maintain close communication with the U.S. and prudently review the matter before making a decision.” 

During a press conference on March 16, Presidential Secretary for Public Affairs and Communications Lee Kyu-yeon reiterated Seoul’s ambiguous position, remarking, “This is an issue that should be decided after sufficient discussions between Korea and the U.S. and with adequate time for deliberation, and I understand that the two sides remain in close communication… We intend to handle this issue very carefully.” 

Foreign Minister Cho Hyun maintained that ambivalent stance during a plenary session of the National Assembly’s Foreign Affairs and Unification Committee on March 17. When legislators asked whether Washington had formally requested a deployment, he responded, “It’s a situation where one could say it is a request or not… As for whether discussions on deployment itself have taken place with the U.S. side, I find it difficult to provide an answer at this point.” 

Since it remains unclear whether the U.S. government has made a formal request, aside from Trump’s remarks on social media, Seoul is biding its time to gauge the responses of other allies and ascertain Washington’s official stance.

Lee is grappling with the same dilemma his predecessor, Roh Moo-hyun, faced in 2003 over whether to dispatch South Korean troops to Iraq. Following the U.S. invasion of Iraq in 2003, Washington pressed its allies to provide reinforcements and troop contributions in support of its war effort. Initially, amid widespread anti-American public sentiment and in line with his “Northeast Asian Balancer” policy and pro-autonomy orientation, Roh was hesitant to acquiesce to Washington’s demands. Not only did Roh’s progressive support base in the National Assembly and among civil societies oppose the dispatch of troops, but broader public sentiment was also strongly negative.

At the time, an interministerial rift emerged within Roh’s Cabinet between a “self-reliance” faction, led by the National Security Council (NSC) and Ministry of Unification, which opposed the troop dispatch, and a “pro-alliance” faction, centered around the Ministry of Foreign Affairs and the Ministry of National Defense, which supported it. Due to the bureaucratic embeddedness and “institutional stickiness” of the decades-long South Korea-U.S. alliance, Roh’s pursuit of greater autonomy was ultimately derailed, and South Korea realigned with Washington. 

Roh, along with the National Assembly, ultimately approved the deployment of 3,600 South Korean troops to Iraq, albeit under a strictly non-combat and humanitarian mandate. The rationale was threefold: to gain greater leverage in negotiations with Washington over the stationing of U.S. forces in Korea, to bolster South Korea’s position in talks with Pyongyang on its nuclear program, and to capitalize on economic opportunities in Iraq’s reconstruction.

However, unlike the U.S. invasion of Iraq in 2003, Washington’s 2026 attack on Iran does not enjoy the same degree of legitimacy or allied support, largely due to the lack of prior consultation with its partners. Moreover, Washington’s overall objective in Iran remains unclear, whether it is regime change or nuclear dismantlement. This ambiguity helps explain why U.S. allies have been more reluctant to dispatch warships to the Strait of Hormuz. In this context, Lee faces an even more difficult position as he buys time to decide whether to comply with Trump’s request.

Concurrently, South Korea faces several domestic hurdles, including the requirement for parliamentary approval to deploy warships overseas. On this issue, both the ruling Democratic Party of Korea and the main opposition People Power Party have made it clear that, by law, the deployment of warships for combat operations requires legislative approval and oversight. Nonetheless, Lee has the executive authority to directly involve South Korea in the U.S.-led maritime operation without parliamentary approval, as Seoul already maintains a deployed anti-piracy force, the Cheonghae Unit, in the Gulf of Aden, which could readily expand its operational scope to include the Strait of Hormuz.

One option short of fully committing South Korea to the maritime operation would be for Lee to provide limited support by escorting Korean and allied commercial freights through the waterway. In what may prove to be a defining test of his pragmatic diplomacy, Lee must tread carefully, doing enough to satisfy Washington’s demands while gauging the actions of other allies and acting in concert to avoid being drawn into the wider war in the Middle East.

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The South Korea-U.S. alliance is being put to the test again amid U.S. President Donald Trump’s repeated call for South Korea to deploy warships to the Strait of Hormuz. On March 14, Trump urged several countries to send warships to the critical maritime chokepoint in an effort to reopen the blockaded passage. On his Truth Social platform he wrote, “Hopefully China, France, Japan, South Korea, the UK, and others, that are affected by this artificial constraint, will send Ships to the area so that the Hormuz Strait will no longer be a threat by a Nation that has been totally decapitated.” 

Trump’s request for warships has put South Korea and its allies in a strategic dilemma. So far, allied nations have been hesitant to commit warships to the passage and have instead been weighing their options. However, as Trump’s patience grows thin and the pressure of alliance expectations mounts, the window for strategic ambiguity is closing. On March 15, Trump intensified pressure on his allies, warning, “Whether we get support or not, I can say this – and I said it to them: we will remember.”

Dubbed the world’s “energy artery,” the Strait of Hormuz is responsible for the passage of approximately a fifth of the world’s crude oil and a third of liquefied natural gas (LNG). Iran’s blockage of this key maritime passage has pushed oil prices above $100 per barrel, hitting energy-import-dependent countries such as South Korea particularly hard.

Asian countries overall import roughly 60 percent of their oil from the Middle East, with dependence reaching approximately 70 percent for South Korea and 75 percent for Japan. The global energy crisis has posed a significant risk to South Korea’s economy by disrupting its high-tech and manufacturing industries. 

South Korean President Lee Jae-myung faces a difficult dilemma as he seeks to uphold the alliance and reaffirm Seoul’s commitment to Washington amid ongoing trade negotiations, while also maintaining cordial relations with Middle Eastern countries. On one hand, failing to satisfy Washington’s demands could strain the alliance and result in consequences in the form of weaponized interdependence and economic statecraft. 

On the other hand, there is a growing chorus of concerns in Seoul that becoming directly involved in the U.S.-led maritime operation by deploying warships could provoke retaliation from Tehran and jeopardize Korean commercial and industrial interests in the Middle East. Creating unnecessary friction with Iran and becoming militarily embroiled in the Middle East does not align with Lee’s pragmatic diplomatic approach, particularly as $68 billion worth of South Korean corporate projects in the region are already at risk. In fact, several South Korean conglomerates, including Samsung, SK, and Hyundai Motor, currently operate around 140 overseas subsidiaries across the region.

For now, South Korea has adopted a more cautious stance as it assesses the evolving situation, seeking to avoid becoming entrapped in an unwanted conflict with Iran. In response to Trump’s request, a Blue House official stated, “We will maintain close communication with the U.S. and prudently review the matter before making a decision.” 

During a press conference on March 16, Presidential Secretary for Public Affairs and Communications Lee Kyu-yeon reiterated Seoul’s ambiguous position, remarking, “This is an issue that should be decided after sufficient discussions between Korea and the U.S. and with adequate time for deliberation, and I understand that the two sides remain in close communication… We intend to handle this issue very carefully.” 

Foreign Minister Cho Hyun maintained that ambivalent stance during a plenary session of the National Assembly’s Foreign Affairs and Unification Committee on March 17. When legislators asked whether Washington had formally requested a deployment, he responded, “It’s a situation where one could say it is a request or not… As for whether discussions on deployment itself have taken place with the U.S. side, I find it difficult to provide an answer at this point.” 

Since it remains unclear whether the U.S. government has made a formal request, aside from Trump’s remarks on social media, Seoul is biding its time to gauge the responses of other allies and ascertain Washington’s official stance.

Lee is grappling with the same dilemma his predecessor, Roh Moo-hyun, faced in 2003 over whether to dispatch South Korean troops to Iraq. Following the U.S. invasion of Iraq in 2003, Washington pressed its allies to provide reinforcements and troop contributions in support of its war effort. Initially, amid widespread anti-American public sentiment and in line with his “Northeast Asian Balancer” policy and pro-autonomy orientation, Roh was hesitant to acquiesce to Washington’s demands. Not only did Roh’s progressive support base in the National Assembly and among civil societies oppose the dispatch of troops, but broader public sentiment was also strongly negative.

At the time, an interministerial rift emerged within Roh’s Cabinet between a “self-reliance” faction, led by the National Security Council (NSC) and Ministry of Unification, which opposed the troop dispatch, and a “pro-alliance” faction, centered around the Ministry of Foreign Affairs and the Ministry of National Defense, which supported it. Due to the bureaucratic embeddedness and “institutional stickiness” of the decades-long South Korea-U.S. alliance, Roh’s pursuit of greater autonomy was ultimately derailed, and South Korea realigned with Washington. 

Roh, along with the National Assembly, ultimately approved the deployment of 3,600 South Korean troops to Iraq, albeit under a strictly non-combat and humanitarian mandate. The rationale was threefold: to gain greater leverage in negotiations with Washington over the stationing of U.S. forces in Korea, to bolster South Korea’s position in talks with Pyongyang on its nuclear program, and to capitalize on economic opportunities in Iraq’s reconstruction.

However, unlike the U.S. invasion of Iraq in 2003, Washington’s 2026 attack on Iran does not enjoy the same degree of legitimacy or allied support, largely due to the lack of prior consultation with its partners. Moreover, Washington’s overall objective in Iran remains unclear, whether it is regime change or nuclear dismantlement. This ambiguity helps explain why U.S. allies have been more reluctant to dispatch warships to the Strait of Hormuz. In this context, Lee faces an even more difficult position as he buys time to decide whether to comply with Trump’s request.

Concurrently, South Korea faces several domestic hurdles, including the requirement for parliamentary approval to deploy warships overseas. On this issue, both the ruling Democratic Party of Korea and the main opposition People Power Party have made it clear that, by law, the deployment of warships for combat operations requires legislative approval and oversight. Nonetheless, Lee has the executive authority to directly involve South Korea in the U.S.-led maritime operation without parliamentary approval, as Seoul already maintains a deployed anti-piracy force, the Cheonghae Unit, in the Gulf of Aden, which could readily expand its operational scope to include the Strait of Hormuz.

One option short of fully committing South Korea to the maritime operation would be for Lee to provide limited support by escorting Korean and allied commercial freights through the waterway. In what may prove to be a defining test of his pragmatic diplomacy, Lee must tread carefully, doing enough to satisfy Washington’s demands while gauging the actions of other allies and acting in concert to avoid being drawn into the wider war in the Middle East.

Yoonki Lee is an MPhil student in International Relations at the University of Oxford. He graduated summa cum laude from Yonsei University with a BA in International Studies.

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