South Korea comes under US nuclear umbrella in bid to 'restrain adventurism' by North's Kim Jong-un

South Korea has set aside the consideration of pursuing its own nuclear arsenal in return for strengthened US commitment to protect Seoul under its nuclear umbrella against mounting threats by Pyongyang, analysts said.

Thursday's "Washington Declaration", announced at the end of President Yoon Suk-yeol's six-day visit to Washington, reaffirmed South Korea's long-standing commitment to its obligations under the Nuclear Nonproliferation Treaty (NPT), in return for "regular visibility" of US strategic assets to the Korean peninsula, including the upcoming visit of an American nuclear ballistic missile submarine to South Korea.

The statement said the two allies would set up a Nuclear Consultative Group to discuss ways to cope with North Korea's threats, through which Seoul would be granted a greater voice in planning for the use of nuclear weapons in any conflict with Pyongyang.

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Analysts noted South Korea was also hoping to avoid further angering Russia and China, with the joint release mitigating Yoon's earlier remarks concerning the war in Ukraine and tensions in the Taiwan Strait.

Yoon's summit with US President Joe Biden drew keen international interest, partly as Beijing and Seoul had recently exchanged harsh words over Yoon's remarks in a Reuters interview last week, whereby he blamed tensions in the Taiwan Strait on "an attempt to change the status quo by force", although he did not refer to China by name.

Yoon also likened the issue of Taiwan - a self-governed island viewed by mainland China as a renegade province - to North Korea and South Korea, defining it as a global issue, which sparked anger in Beijing.

Furthermore, the South Korean leader told Reuters that his government would consider sending lethal weapons to Kyiv in the event of a major new attack against Ukraine civilians, leading to angry comments by Moscow.

Kim Joon-hyung, former head of the Korea National Diplomatic Academy, said a key point from this week's Washington summit was that South Korea had renewed its pledge to abide by the NPT, thereby "depriving itself of an option to arm itself with its own nuclear weapons".

He said the agreement would "help quell voices calling for the South to have its own nuclear arsenal", a move Yoon appeared to embrace earlier this year in the face of intensifying missile tests, including intercontinental ballistic missiles, by the North, he said.

The US pledged to increase South Korea's involvement in implementing extended deterrence via mutual consultations, information sharing, simulations, combined defence exercises and the visibility of American strategic assets.

"The declaration is clear that the Yoon government has confidence in the US nuclear umbrella and recognises both the necessity and benefits of continuing to rely on it," said Leif-Eric Easley, a political-science professor at Ewha University in Seoul.

Moon Seong-mook, a senior researcher at the think tank Institute for National Security Strategy, said the Washington Declaration marked the first US commitment clearly written down that provided a nuclear umbrella and an extended nuclear deterrence mobilising all of its military capabilities, including nuclear, to defend its ally.

He also noted that at a post-summit press conference, Biden said a nuclear attack by the North against the US or its allies would "result in the end of whatever regime".

"This statement will help restrain [North Korean leader] Kim Jong-un's adventurism," Moon said.

But Frank Aum, a senior expert on Northeast Asian affairs at the US Institute of Peace, said the Washington Declaration itself may not provide any "actual security benefits" in terms of deterring North Korea.

"The existing combined conventional and nuclear capabilities of the US-South Korea alliance were already sufficient in deterring major North Korean attacks. Anything more risks escalating the tensions and arms racing that the peninsula has witnessed over the last decade," he was quoted as saying by Yonhap news agency.

Anthony Ruggiero, former director for North Korea at the US National Security Council, said the declaration "fails to address North Korea's expanding nuclear weapons and ballistic missile programme", according to Yonhap.

Yang Moo-jin, a political-science professor at the University of North Korean Studies in Seoul, said the latest joint statement differed from earlier ones as it emphasised the military means to cope with the North more than economic incentives and dialogue.

"The North won't simply succumb to pressure and give up nuclear weapons. The tighter the United States and South Korea close ranks, the more difficult it would be for them to draw cooperation from China and Russia for denuclearisation," he said.

US nuclear-armed submarines often went to South Korea during the Cold War, when Washington had many nuclear warheads stationed in the Asian country, but they were all withdrawn in 1991. Soon after, South and North Korea pledged not to test, manufacture, produce, receive, possess, store, deploy or use nuclear weapons, an agreement that has been regularly violated by Pyongyang.

On the question of Ukraine, Thursday's joint statement said the US and South Korea "condemned in the strongest possible terms" Russia's actions against civilians and critical infrastructure and were continuing to support Kyiv with "political, security, humanitarian, and economic assistance".

But the statement stopped short of mentioning South Korea's possible offering of lethal weapons to President Volodymyr Zelensky's government.

Yoon and Biden also "strongly opposed any unilateral attempts to change the status quo in the Indo-Pacific, including through unlawful maritime claims, the militarisation of reclaimed features, and coercive activities", the joint statement said.

However, it did not refer to China by name and conspicuously omitted the words "by force" in apparent deference to China's mood, analysts said.

"The [latest] statement is somewhat mitigating Yoon's earlier remarks concerning China and Russia," said political science professor Park Won-gon of the Ewha Womans University.

He added it was "rather similar" to earlier joint statements made by the US and South Korea, and the US, Japan and South Korea, last year.

"In the first place, Yoon has no intention to antagonise China," Park added.

Despite the diplomatic spat between South Korea and China over Yoon's recent comments, Seoul's new ambassador to China, Chung Jae-ho, on Monday delivered Yoon's invitation to Chinese President Xi Jinping to visit Seoul within the year.

Yoon's message also included greetings to Xi and a request for continued interest and support for South Korean firms operating in China, South Korea's KBS TV said.

In response, Xi welcomed the newly appointed envoy and wished him well in his new role, the network said.

This article originally appeared on the South China Morning Post (SCMP).

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