President Yoon Suk Yeol went to Washington to reset South Korean diplomacy by drawing closer to the United States and taking a larger role on the international stage. If the warmth of his reception there was the gauge of success, he did well.
President Biden welcomed him as “my friend.” Mr. Yoon belted out “American Pie” while the crowd whooped along during the White House dinner. On Thursday, he addressed the United States Congress, thanking Americans for their support during the Korean War, and extolling a deep relationship between the countries that helped energize South Korea’s rise to become a global technological and cultural powerhouse.
“Even if you didn’t know my name, you may know BTS and Blackpink,” Mr. Yoon said to chuckles from American lawmakers. “BTS beat me to the White House. But I beat them to Capitol Hill.”
But Mr. Yoon now returns home to South Korea to a decidedly colder audience — a public that has punished him with low approval ratings and, in some sectors, has deep misgivings over a pivot toward the United States that could alienate China and threaten the country’s long tradition of diplomatic caution.
Even before Mr. Yoon departed for Washington, South Koreans were beginning to grapple with questions that seemed distant until recently. How can they feel safe under the rapidly expanding nuclear threat from North Korea? And how should they navigate the increasingly bitter rivalry between the United States, South Korea’s main military ally, and China, its biggest trading partner?
The main answer Mr. Yoon is bringing home is the “Washington Declaration,” a joint statement with Mr. Biden. In it, Mr. Biden promised that Washington would embrace South Korea as a close consultative partner in its nuclear strategy over the Korean Peninsula — though American presidents will remain the sole authority on whether to actually use nuclear weapons.
To show its “extended deterrence” commitment to defend its ally with nuclear weapons if necessary, Mr. Biden promised that U.S. nuclear ballistic missile submarines would make port calls in South Korea for the first time in decades. In return, Mr. Yoon reaffirmed South Korea’s intention not to develop nuclear weapons of its own, dispelling misgivings in Washington that he might consider a nuclear option, as he indicated he might early this year.
But like everything else Mr. Yoon has done since his election last year, the reviews in South Korea were polarized.
“History will remember the Yoon government as the first South Korean administration to recognize the North Korean nuclear program as a present and urgent threat and begin preparing responses to the crisis,” said Cheon Seong-whun, a former head of the Korea Institute for National Unification in Seoul.
The Washington Declaration was “a big win” for South Korea because “for the first time, the allies are discussing nuclear deterrence, which Seoul has not been able to discuss with Washington until now,” said Kim Duyeon, a Seoul-based researcher for the Center for a New American Security.
“They are gaming out scenarios in which not only North Korea might use a nuclear weapon but the U.S. would direct the employment of a nuclear weapon in response as well,” Ms. Kim said. “This is huge because until now, the tabletop exercises would end before Washington decides to use a nuclear weapon. The U.S. had considered such information to be too classified to share and because nuclear use would be a U.S. decision, operation and execution plan.”
Mr. Yoon’s critics at home, however, felt he was giving away too much for too little, seeing the declaration and a separate joint statement from Mr. Yoon and Mr. Biden as a carefully wrought design to silence calls for South Korea’s own nuclear force or the redeployment of American tactical nuclear weapons in the South.
Such calls have gained momentum in recent months, as North Korea has stoked nuclear jitters in the South by testing a series of what it called nuclear-capable short-range ballistic missiles. The North has also warned that first nuclear strikes were now part of its military strategy.
“The Washington Declaration may look substantive and fantastic, but, in reality, it is an empty shell,” said Professor Kim Dong-yub, at the University of North Korean Studies in Seoul. “There is no change in Washington policy.”
Critics also doubted that the port calls by U.S. nuclear submarines would do much more than further escalate regional tensions with China and North Korea and provide another excuse for the North to expand its nuclear arsenal. On Saturday, North Korea called Mr. Yoon “a fool” and Mr. Biden “an old man with no future” and said it felt compelled to take “more decisive action.”
“They are not ‘extended deterrence,’ but rather ‘extended crisis,’” Mr. Kim said.
An editorial in the conservative daily Chosun Ilbo sounded miffed by what it called the Biden administration’s efforts to “tighten the nuclear shackles” on its ally.
“The declaration seems to put more emphasis on American concerns that South Korea could develop its own nuclear weapons than on the North Korean nuclear threat that prompts such aspirations,” it said. “Ultimately, South Korea must be in a position to defend itself.”
For decades, South Korea’s defense strategy relied on the assumption that the United States would come to its aid if war were to break out. But the once-bedrock premise is losing its credibility. In a survey by the Seoul-based Chey Institute for Advanced Studies late last year, nearly 49 percent of respondents said they doubted that Washington would fight for South Korea at the risk of a North Korean nuclear attack on mainland United States. Nearly 77 percent said South Korea needed to develop its own nuclear arsenal.
To such skeptical South Koreans, Washington’s promise of extended deterrence “just amounts to rhetoric, however you package it,” said Lee Byong-chul, a researcher on nuclear policy at the Institute for Far Eastern Studies at Kyungnam University in Seoul.
Many South Koreans remain wary of great powers, reflecting their deep grievances over Japanese colonial rule and the division of the Korean Peninsula by the Soviet Union and the United States at the end of World War II.
South Korea has kept Japan at arm’s length, even though Washington urged its two key allies to work closely together to deter China and North Korea. It has also sought diplomatic balance between Washington and Beijing. Its more progressive leaders, like Mr. Yoon’s predecessor, Moon Jae-in, doggedly pursued dialogue with North Korea, even causing friction with Washington, which tended to emphasize sanctions.
Mr. Yoon, however, has made a point of shaking the traditional equilibrium.
In March, he broke a logjam in relations with Japan by promising that Seoul will no longer seek compensation for victims of forced labor during Japan’s colonial rule. Mr. Yoon also doggedly aligned Seoul more closely with the United States, despite concerns about China’s ability to harm South Korea’s vital economy.
“The alliance has now become a global alliance that safeguards freedom and peace around the world,” he told the U.S. Congress. “Korea will fulfill its responsibilities.”
While in Washington, Mr. Yoon condemned the war against Ukraine as “a violation of international law.” In a jab at Beijing, he opposed “any unilateral attempts to change the status quo in the Indo-Pacific, including through unlawful maritime claims, the militarization of reclaimed features and coercive activities.”
Liberal South Koreans cautioned against Mr. Yoon’s approach.
“If South Korea is unilaterally sucked into the new U.S.-led Cold War system, it must face up to the reality that relations with China and Russia, both of which have a strong influence on North Korea, will become more dangerous, and the risk of a North Korean nuclear crisis and even war on or around the peninsula will increase,” the liberal Hankyoreh newspaper said.
Both hawks and doves in policy circles in Seoul will have reason to feel disappointed by the Washington Declaration, which “neither signals a push for dialogue with Pyongyang nor promises Seoul getting a nuclear deterrent of its own,” said John Delury, an East Asia scholar at Yonsei University in Seoul.
But to many South Koreans, especially younger generations struggling with dwindling job opportunities, a more pressing issue than the North’s nuclear arsenal is the economy.
In recent months, hardly a day has gone by in South Korea without headlines blaring concern that Mr. Biden’s Inflation Reduction and Chips and Science Acts would hurt two of South Korea’s most important industries: electric cars and semiconductors. But in their joint statement, Mr. Yoon and Mr. Biden only agreed to “continue close consultations.”
“Younger Koreans don’t know the lyrics to ‘American Pie,’ but they know about the Inflation Reduction Act,” Mr. Delury said.