With Trump, Asia’s nuclear crisis expands

Next to North Korea and fearing U.S. abandonment, South Korea and Japan weigh their own options.The nuclear crisis in Northeast Asia was bound to be one of the most dangerous challenges facing the next U.S. president, no matter who won on Tuesday. With Donald Trump’s surprise victory, though, it could metastasize in dramatic ways:  If you thought North Korea’s nuclear march was disconcerting, consider that South Korea and Japan may now pursue nuclear programs of their own, raising the risks and stakes of war not only with North Korea but China too.
Mr. Trump repeatedly endorsed such a nuclear proliferation cascade on the campaign trail. “At some point we have to say you know what? we’re better off if Japan protects itself against this maniac in North Korea, we’re better off, frankly, if South Korea is going to start to protect itself,” he said.
This was a corollary to his threats to pull U.S. troops from Japan and South Korea, where they’ve helped secure peace for more than six decades, if those countries don’t start spending dramatically more on their own defense. It’s possible Mr. Trump will drop his enthusiasm for South Korean and Japanese nuclearization upon entering the Oval Office. His campaign advisers tended to ignore the subject in public statements, likely a reflection of the decades-old bipartisan consensus against nuclear proliferation in Washington. But as with other issues, the approach of President Trump will depend on who he brings into the White House for advice, and whether he listens to them.
Cheong Seong-chang will be calling for South Korean nuclearization either way. Speaking in Seoul last week, before America voted, the soft-spoken scholar and government advisor argued that his country needs nukes to defend itself, that a majority of his countrymen agree, and that skeptics in government will embrace the view sooner or later. Sooner if a Trump administration backs it, he says, but within a decade regardless. Two months ago Mr. Cheong and other security, diplomatic and engineering experts launched the Nuclear Research Group for Korea to study Seoul’s options. A similar group was established in the early 1990s, he says, but disbanded within a few years “under heavy social pressure” because it was “politically incorrect” to broach the nuclear issue. Today that taboo is gone.
Since January North Korea has conducted two nuclear tests, its fourth and fifth overall, and likely moved closer to a hydrogen-bomb capability that threatens to “wipe out all of Seoul,” Mr. Cheong notes. It has also tested more than 20 ballistic missiles, at least one of which could threaten the U.S. homeland, and completed its first successful submarine and road-mobile launches. Analysts figure it could have 100 bombs by 2020, before the first Trump term is up.
Mr. Cheong argues that at this point North Korea won’t let its nuclear program be rolled back diplomatically, “no matter how many sanctions we impose.” China’s policy of protecting its ally from collapse “will remain unchanged.” And when Pyongyang inevitably acquires a credible capability to hit the U.S. with nuclear-tipped missiles, “the U.S. will have no choice but to come to the negotiating table” and sue for peace. This will yield, “if not a total abandonment of South Korea,” then a bargain aimed at mere containment: “If North Korea has 50 nuclear weapons, and promises not to build any more, and to suspend missile tests, the U.S. will strike a deal.” Tensions between Pyongyang and Washington may cool, he says, “but South Korea will continue to be held hostage.” Hence the need to go nuclear. South Korea’s civilian nuclear infrastructure24 plants providing 30% of the country’s energy could be used to produce 5,000 bombs worth of fissile material, Mr. Cheong says, dwarfing Pyongyang’s capability. Embracing the necessary technologies, including plutonium reprocessing, could be “the game-changer that will enable South Korea to manage North Korean problems.”
It would also “be consistent with U.S. security interests,” Mr. Cheong says, and “contain the nuclear issue within the boundary of the Korean Peninsula.” These are the claims that put him most at odds with longstanding thinking in Washington, where leaders generally fear that South Korea going nuclear could shatter the U.S.-South Korean alliance, spark a war with the North and trigger follow-on nuclearization in Japan and maybe Taiwan developments China is liable to protest with military force.  Mr. Cheong thinks certain compromises can make it all work. Seoul would go nuclear but also engage Pyongyang economically and diplomatically, assuring Kim Jong Un that no one seeks his demise.
Seoul would build only as many bombs as needed to have an edge (“if the North has 30, we have 40, for example”). And Seoul would ask the U.S. to “co-manage” its arsenal, preserving the bilateral alliance while assuring China and Russia that South Koreans have ultimate control over the weapons.
Japan may indeed seek to go nuclear, Mr. Cheong acknowledges, but it too could placate its rivals by keeping its arsenal small and co-managed. “The U.S. should assure China that Japan will not build more than a certain number of nuclear weapons large enough to counter the North Korean threat,” allowing China to “maintain its nuclear advantage over other Asian countries.”
Taiwan, for its part, has to sit on its hands. Such prescriptions seem rather tidy given all the uncertainties and dangers involved, and for years Seoul and Washington could dismiss them as non-starters. Even as majorities of South Koreans have told pollsters since the 1990s that they support nuclearization, policy makers in both capitals have been overwhelmingly opposed. That may no longer be so. Several potential candidates in South Korea’s looming presidential election back nuclearization, including former National Assembly floor leader Won Yoo-cheol and Nam Kyung-pil, governor of the country’s most populous province. Mr. Cheong, who acknowledges that “experts and technocrats have tended to be against going nuclear,” says that officials have privately expressed greater interest since Pyongyang’s latest nuclear test in September.
Once Pyongyang completes a hydrogen bomb, he says, “many experts will switch their views.” Then there’s Donald Trump. If he sticks to supporting South Korean and Japanese nuclearization, he might as well hold a bonfire of traditional U.S. non-proliferation dogmas on the White House lawn.
Even if he reverses course, though, his record of denigrating U.S. allies has already made South Koreans and others more fearful of abandonment and therefore more likely to hedge their bets and consider going nuclear, despite the costs.  Mr. Trump reportedly had a good phone call with South Korea’s president Wednesday night, but it’s no surprise that headlines this week in Seoul are blaring about “shock” and “panic.” As Mr. Cheong predicted last week: A Trump presidency “will reshape the security landscape of Northeast Asia.”
Mr. Feith is a Journal editorial writer based in Hong Kong.