South Korea Gets New Nuclear Assurances From U.S. Amid Rising Tensions

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President Joe Biden renewed America’s promise to protect South Korea against nuclear attack Wednesday through a series of security measures aimed at countering North Korea.

The pledge comes amid Pyongyang’s advancements in a decades-long march to wield nuclear-tipped missiles capable of striking targets on the Korean Peninsula and continental United States. The focus on deterrence and dependence on the U.S. nuclear umbrella, rather than diplomacy, underscores how little the U.S. has achieved in its long struggle to curtail Pyongyang’s missile and nuclear programs.

North Korean leader Kim Jong Un said this month he intends to expand the isolated nation’s arsenal to “constantly strike extreme uneasiness and horror” in adversaries. Just this month, North Korea launched its first solid-fuel intercontinental ballistic missile, a major technological achievement because it takes less preparation time to launch and is therefore harder to detect. The Biden Administration has made multiple public overtures to meet North Korean officials without preconditions. But the Kim regime has thus far ignored them after failing to reach a deal with President Donald Trump during a détente in 2018. Since then, North Korea has proceeded with missile tests at a record-setting pace.

Read More: Is The Biden Administration’s Policy Toward North Korea Working?

With fears of confrontation mounting, South Korean President Yoon Suk Yeol visited the White House Wednesday for a state visit. Yoon and Biden signed a joint document, dubbed the “Washington Declaration,” which includes initiatives that reinforce America’s longstanding pledges to protect and respond to any North Korean attack.

Among the guarantees contained in the agreement was a commitment by the U.S. to send Navy nuclear-armed submarines for port visits in South Korea for the first time in more than 40 years. The declaration also established a consultation group tasked with responding to North Korean nuclear attacks, and included provisions to enhance information-sharing as well as military joint-exercises.

“A nuclear attack by North Korea against the United States or its allies and partners is unacceptable and will result in the end of whatever regime would take such an action,” Biden said alongside Yoon during a press conference in the White House Rose Garden. “As commander-in-chief, I have the sole authority to use a nuclear weapon, but what the declaration means is that we’re going to make every effort to consult with our allies when it’s appropriate.”

Biden South Korea President
South Korea's President Yoon Suk Yeol stands with President Biden on the South Lawn of The White House in Washington, DC on April 26, 2023.Oliver Contreras—Sipa USA/AP

Estimates vary, but analysts say North Korea has produced enough fissile material for between 20 to 60 warheads to go along with an arsenal of several hundred short- and medium-range ballistic-missiles capable of hitting South Korea, Japan, and U.S. military bases and territories in the region. The lack of progress to halt Kim’s growing arsenal has stoked concerns in South Korea about whether and how the nation can defend itself if war were to break out.

The new agreement between Seoul and Washington includes confidence-building language and steps to reinforce what’s known as “extended deterrence”—America’s willingness to use nuclear weapons, if necessary, to defend South Korea. “We want to customize our response against North Korea’s nuclear threat based on extended deterrence,” Yoon said at the press conference. Achieving peace with Pyongyang will come through the “superiority of overwhelming forces,” not the goodwill of North Korea’s leader, he added.

A majority of South Koreans want the country to develop a nuclear capability of its own or host U.S. weapons again at bases inside the country. A poll published by the Chicago Council on Global Affairs in February 2022 found that 71% of South Koreans favor developing their own nuclear weapon, while 56% wanted to once again host American nukes, which were based on the peninsula for decades before being removed in 1991.

The White House insists it has no plans to reintroduce shorter-range nuclear weapons in South Korea. “There is no vision of returning U.S. tactical or any other kind of nuclear weapon to the Korean peninsula as there was in the Cold War,” one Administration official, who spoke on the condition of anonymity ahead of Yoon’s visit, told reporters. The stance has been embraced by both Republican and Democratic Administrations, which maintain that such a move is antagonistic and unnecessary.

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South Korea is a signatory to the Nuclear Nonproliferation Treaty, an international agreement wherein nations without nuclear weapons agree never to obtain them. But Yoon has embraced a hard-line policy on North Korea, and has, at times, raised the possibility of pursuing an independent nuclear path.

“It appears to me that the Yoon government is patronizing such movements as a way of enhancing its bargaining leverage on the U.S. for its fuller assurance of extended deterrence,” says Moon Chung-in, who advised former South Korean President Moon Jae-in on national security and foreign affairs.

“The new nuclear accord will be more symbolic than real,” he says. “In my personal view, it is not for Pyongyang, but for Seoul, aiming at particularly those South Koreans who worry about the credibility of the American nuclear umbrella. North Koreans have always thought American extended deterrence has been working well and threatens them.”

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