Commentary: The South Korean nuclear debate won’t go away

BUSAN, South Korea: Earlier last year, South Korean President Yoon Suk Yeol suggested there may come a time when Seoul may have to consider developing a nuclear arsenal of its own if North Korea’s nuclear threat grows.
Although South Korean officials were quick to walk back on Mr Yoon’s comments, there was no putting the genie back into the bottle. South Korean public support for nuclearisation is the highest it has ever been; 71 per cent of South Koreans think the country should acquire nuclear weapons.
Earlier this year, the South’s largest circulation newspaper issued editorials demanding the same. So did a major South Korea national security think tank.
And last week, South Korea’s defence minister nominee Kim Yong-hyun spoke approvingly of the possibility of acquiring nuclear weapons. 
The nuclear debate was supposed to have ended last year. Then, South Korea signed a major deal with its United States ally, recommitting South Korea to its non-nuclear status in exchange for tighter US security guarantees. The US strongly opposes the nuclearisation of any currently non-nuclear state, including its own allies.
But North Korea has a growing nuclear and missile programme. South Korea currently stalemates that arsenal via US “extended deterrence”. That is, the US counters the North’s nuclear threat on South Korea’s behalf; South Korea does not do so with its own nuclear weapons.
That places a lot of trust in the US to come through for South Korea in a potentially nuclear situation. South Korea’s ongoing nuclear interest suggests that trust has eroded.
For decades, the US commitment to South Korean security was highly credible. In the words of US decision makers, American guarantees were “‘ironclad”.
When the North Korean threat to South Korea – and US regional bases – was conventional, that commitment was low risk. The brunt of a second Korean War would fall on Koreans. The US commitment on the ground would be small. Most of American support would be from air and sea. US exposure would be limited.
All this began to change under the leadership of current North Korean leader Kim Jong Un. Mr Kim’s father and grandfather evinced interest in nuclear weapons and the missiles to carry them.
Mr Kim’s father was in charge when the North conducted its first nuclear test in 2006. But those previous Kims did not build a long-range missile force or that many nuclear warheads. Perhaps they were technologically constrained, or perhaps they were hoping restraint would help them capture a deal with Washington and Seoul. Whatever the reasons, the current Kim is not so restrained. He has significantly accelerated the nuclear and missile programme.
North Korea today has intercontinental ballistic missiles (ICBMs) with the range to strike as far as the United States. It also has medium-range missiles that can reach Guam – a US territory. And it has probably at least 50 nuclear warheads. Those nuclear-tipped ICBMs now pose a direct threat to the US homeland. This is new in the US alliance with South Korea.
Where before, US exposure was mostly limited to conventional weapon effects on the peninsula, North Korea can now threaten mass US civilian casualties should the US join a future Korean conflict.
The result of this greatly expanded North Korean capability is credibility anxieties about the US commitment. If North Korea can nuke the US homeland, will the US automatically meet its alliance commitments to the South? Will it join a war without hesitation? It might, of course, and American officials signal relentlessly that it will.
But it might also hesitate. We know, for example, that former president John Kennedy was far more willing to make concessions to the Soviet Union during the Cuban missile crisis than was known at the time.
We can also see hesitation in the Western response to Russia’s invasion of Ukraine. The US and its North Atlantic Treaty Organization (NATO) allies have not fully supported Ukraine, because they fear Russian nuclear escalation. Ukraine and its supporters have complained bitterly that Russian nuclear threats have unnecessarily crippled Ukraine’s defence. One might imagine a similar US hesitation in a Korean scenario.
South Korea is a treaty ally, of course. Ukraine is not. And South Korea has a US military presence, which Ukraine also does not. So that suggests greater US credibility.
But still, the US commitment was instituted, and persisted for decades, around a regionally contained conventional threat. That has changed dramatically, for the worse, in the last decade. So it is simply not as clear as it once was how the US would respond in a Korean crisis. North Korea would almost certainly make the same nuclear threats Russia is now making.
Given all this, the South Korean public and a growing number of elites want the South to be able to counterpoint North Korean nukes on its own – local deterrence instead of extended deterrence.
South Korea’s nuclear dilemma will only get worse, so the pressure to nuclearise will likely rise. The world has heard North Korea make aggressive, outlandish nuclear threats for more than a decade. It has said again and again that it will not denuclearise. South Korea’s fear that the US might hesitate, as it has in Ukraine, is not unfounded.
South Korean nukes are not the only possible answer. Missile defense technologies might prove themselves at last. If the US and South Korea had reliable missile protection, the alliance-breaking threat of Northern ICBMs would be less sharp. Or, negotiations with North Korea might limit its programmes and reduce the threat it poses. But these solutions are far off.
Missile defense is not reliable enough against the sorts of large missile North Korea is building (compared to Israel’s Iron Dome against smaller, slower missiles). And negotiations with North Korea have proven frustratingly inconclusive for decades. Even a personal meeting by former US president Donald Trump with Kim did not return any limits on the North.
The likely outcome is growing South Korean anxiety leading to growing South Korean pressure on the US for tighter commitments. If the US cannot or will not do that, South Korea, like Israel and India before it, may decide that local deterrence is superior to an uncertain US willingness to risk nuclear devastation on its behalf.
Robert Kelly (@Robert_E_Kelly) is a professor of political science at Pusan National University.