South Korea, explained.
South Koreans will be more uneasy about US extended deterrence commitments (Getty Images Plus)
Trump’s transactional approach to alliance politics may close the door for more reassurances, pushing South Korea for a deterrence of its own.
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Why South Korea might go nuclear in Trump’s termWhy South Korea might go nuclear in Trump’s term
Amid unprecedented political turmoil in South Korea, US Secretary of State Antony Blinken this month visited Seoul, expressing confidence in both the South’s democratic credentials and the strength of the US-ROK alliance. This visit, Blinken’s last as Washington’s top diplomat, coincided with two successive missile tests by the Kim Jong-un regime in Pyongyang. Blinken’s references to the alliance and the North’s missile tests are important with regard to their timing. While Blinken’s remarks are meant to assuage Seoul’s fears about the future of the alliance under the incoming Trump administration, Kim’s missile gambit is an effort to exacerbate those.
During Trump’s second term, such attempts by Kim, coupled with his focus on building tactical nuclear weapons, will precipitously increase South Korea’s security concerns. This trepidation will likely push Seoul to get a nuclear deterrent of its own. Beleaguered South Korean president Yoon Suk-yeol flagged this potential last year and in 2023, and even with his political influence diminished, the driver for an independent nuclear deterrent remains.
There are two reasons why this might be the case during Trump’s upcoming tenure.
The foremost reason why South Korea might mull over going nuclear is the unlikelihood of getting more reassurances and extended deterrence commitments from the Trump administration. Statements by Trump and his key nominees suggest that the administration will want more, not less, out of the South. The incoming US president has repeatedly urged South Korea to pay more for its defence. This essentially means that the strength of Washington’s extended deterrence will depend on how profitable certain transactions are.
The protection of South Korea’s territorial integrity is unlikely to be high on Trump’s agenda.
As for the views of Trump’s prospective cabinet members, they are more likely to erode the value and credibility of US extended deterrence. This is primarily because they are centred on shifting US focus away from the Korean Peninsula towards China. Elbridge Colby, the author of The Strategy of Denial: American Defence in an Age of Great Power Conflict and the incoming Undersecretary of Defence for Policy, has, for example, long seen China’s growing military power as the biggest threat that the United States must pay attention to. However, what is more noteworthy apropos of South Korea is that Colby believes it should deal with Kim on its own. In an interview, Colby said “South Korea is going to have to take primary, essentially overwhelming, responsibility for its own self-defence against North Korea because we don’t have a military that can fight North Korea and then be ready to fight China.”
Such views indicate one thing: the protection of South Korea’s territorial integrity is unlikely to be high on Trump’s agenda. This will certainly make South Koreans more uneasy about US extended deterrence commitments. This scepticism is not without reason as, despite giving extended deterrence-related reassurances, the Biden administration also did not commit to automatically using nuclear weapons in response to a nuclear strike by Pyongyang on Seoul. Apart from this ambiguity and the likelihood of deprioritising South Korea, the North’s demonstrated capability to hold US cities hostage will make extended deterrence more unreliable. All this will contribute to making a nuclear option more propitious for the South.
US and South Korean troops during an exercise (Anthony Morales/US Marine Corps)
Another potential development that might force the South to acquire nuclear weapons is the Trump administration engaging in arms control negotiations with the North. Such an eventuality would mean that the United States would be accepting North Korea as a nuclear-possessor. It would resultantly put an end to efforts to denuclearise the Korean Peninsula, leaving South Korea at a disadvantage. Notably, arms control arrangements with the North would contribute to stabilising Washington-Pyongyang nuclear relations without necessarily having any positive effect on Seoul. If anything, Kim will get more emboldened after gaining legitimacy from the United States.
There are several reasons why Trump could adopt such an approach to dealing with Kim. Two among those are quite compelling. First, he might seek to improve his anti-war credentials by leading the way in amicably resolving the Korean conundrum for America. Second, key officials in his administration might argue that the United States does not have the bandwidth to denuclearise the North. They might also enunciate that, by stabilising its relations with the North, the United States can focus on the actual, more serious threat: China.
Taken together, these two considerations may give Trump the incentive to live with a nuclear North Korea. The South might feel that Trump is making peace with Kim at its expense.
All this will certainly not sit well with the South. Its lack of confidence in extended deterrence, coupled with a realisation that the United States has made peace with Kim’s bomb, will only alienate it. Certainly, it could rightly think that it cannot outsource its security. This thinking will resonate with voices that favour a South Korean nuclear deterrent. What’s more, it is unlikely that the Trump administration would do anything substantive to cause the South to rethink. So, unless the Trump administration finds value in reassuring South Korea, that country might commit to building a nuclear deterrent of its own.
About the author
Syed Ali Zia Jaffery
Syed Ali Zia Jaffery is the Deputy Director of the Centre for Security, Strategy and Policy Research (CSSPR), The University of Lahore.
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