When South Korea’s President Moon Jae In greets President Donald Trump at the White House today, their warm smiles will do little to mask the fact that they meet at perhaps the most dangerous moment in the six-decade old U.S.-South Korean alliance. The failure of a quarter-century of diplomacy has left the North Korean dictatorship on the cusp of possessing a nuclear-armed intercontinental ballistic missile. For the first time since 1953, when the United States committed to protecting the South from another invasion from the North, the American homeland will soon come under direct threat from one of the world’s most ruthless regimes.
Of course, the United States is at loggerheads with the Kim regime because of its commitment to the South—the alliance is not a symptom of today’s crisis between Washington and Pyongyang, but the cause. Not only does the United States station well over 20,000 troops on the Korean peninsula; the two militaries are well-integrated and jointly trained. The United States went so far as to deploy tactical nuclear weapons in South Korea until 1991, and continues to extend the so-called “nuclear umbrella” to protect the South. South Korea, in turn, provided the largest contingent of allied troops during the Vietnam War, and 3,000 of its troops fought in Iraq. South Korea also supported Obama-era initiatives such as the G20 and Nuclear Security Summits, and participates in the Proliferation Security Initiative, the International Framework for Nuclear Energy Cooperation, the Global Initiative to Combat Nuclear Terrorism, making it a leader in anti-proliferation activities.
While few believe Kim Jong Un would launch an unprovoked nuclear strike, most seasoned Korea watchers believe that he would no doubt use his arsenal once it became clear he was about to lose any war that broke out. As this risk increases, Washington will find it increasingly difficult to avoid reassessing the country’s multi-decade alliance with South Korea. The threat to American civilians will be magnified to grotesque proportions, simply because Washington continues to promise to help South Korea.
At stake is not just Washington’s commitment to Seoul, but, quite possibly, America’s larger global standing.
The arguments for maintaining a strong South Korean alliance rest on its deterrent effect against North Korea. The Kim regime has repeatedly struck out at the South—see the 2010 sinking of the Korean navy vessel Cheonan that killed 46 sailors and the shelling of Yongpyong Island. Yet the North has refrained from large-scale attacks against either South Korea or Japan, another target of Pyongyang’s ire, despite its significant missile capability and larger military. Washington interprets this as due, at least in part, to the assumption by all parties that a major attack, or full-scale war, would immediately trigger the self-defense clause of the mutual defense treaty between the United States and South Korea. If that is the case, then the U.S. commitment will be even more important: Only a firm U.S. promise to defend the South will deter the North.
But if, on the other hand, the United States decided that the risk to its interests was prohibitively high, abrogating or scaling back the alliance would potentially destabilize Asia and beyond. It would hand the Kim regime a major strategic victory, removing the single greatest deterrent to its aggression. Pyongyang would be emboldened to continue trying to blackmail the United States, South Korea, and Japan, leading to future crises. Stripped of the assurance provided by America’s support, South Korea might wind up capitulating to the North’s demands for open-ended economic assistance, or even stand down some of its forces. Japan would worry that it may be the next to be abandoned by America. Even worse, in the face of a U.S. withdrawal, both Seoul and Tokyo would immediately begin considering developing their own nuclear and missile programs, instigating a nuclear-arms race that would spill over to China, Taiwan, and possibly beyond.
In the event of a reduced American presence in northeast Asia, China would emerge the big winner. Beijing almost certainly would offer Seoul an alliance of its own, further undermining America’s regional web of alliances, likely tipping the Philippines and Malaysia fully into the Chinese camp. Japanese government officials I spoke to expressed their fears that, in the event of the collapse of the U.S.-South Korea alliance, Beijing may even base Chinese warships in Busan, the southern port closest to Japan, giving China a foothold on the territory closest to the Japanese home islands—historically, Japan’s major geopolitical fear. Access to the southern Korean coastline would enhance China’s ability to control the strategic waterways from the South China Sea through the East China Sea and into the Sea of Japan. The Japanese would consider this a grave threat. In response, the U.S. resources diverted from the Korean peninsula might be redeployed to blunt China’s expansion, including a beefing-up of the U.S. Navy in Japan, which would increase Sino-U.S. tensions and the potential for a maritime confrontation in the narrow, strategic Tsushima Strait.
Cutting South Korea adrift would likely also have global repercussions for America. Other nuclear or potential nuclear states would learn from Pyongyang’s success, opening America up to future nuclear blackmail. Just as significantly, walking away from a long-term ally would make the United States seem capricious and untrustworthy; attempting to maintain America’s worldwide alliance system might become impossible, as no reassurances would be sufficient for jittery partners.
Such fears explain the criticism of Donald Trump, precisely for his questioning of the value of Washington’s long-standing alliances with South Korea and other nations, during the 2016 presidential campaign. Experts cautioned that ending U.S. alliance commitments would “unravel the entire post-World War II order,” while seasoned diplomats warned that America was not engaged in an alliance “protection racket,” but rather benefitted from the global stability that engendered trade and globalization since 1945.
Despite his campaign rhetoric, Trump appeared to acknowledge the importance of the South Korean alliance once in office. His administration walked back his more radical suggestions, mollifying the national-security establishment. Both Secretary of Defense Jim Mattis and Secretary of State Rex Tillerson reaffirmed support for the U.S.-South Korea alliance. Even more strikingly, the administration soon made North Korea a critical national-security issue, even claiming that it was the “most urgent” threat facing the United States, and that “all options are on the table” for dealing with the rogue nation.
Yet even if Trump has decided to embrace the South Korean alliance, there are numerous reasons to be worried about the liabilities that come with it.
North Korea, to be clear, poses no existential threat to the United States. This is not the Cold War; Pyongyang is not Moscow. Accepting Mutual Assured Destruction with the Soviets may have seemed the only way to ensure the ultimate survival of the West; that is not the case with North Korea. Putting America’s cities in the bull’s eye of nuclear nations for anything less than a truly existential threat would be foolish.
Another risk of sticking with the alliance is that the long-term strategy of waiting out the Kim regime seems increasingly unrealistic. Not only has Kim Jong Un ruthlessly secured his power since taking over from his father in 2011—the North Korean economy is actually improving, or at least stabilizing. It makes little sense to keep hoping for the regime’s collapse and doubling down on a failed policy.
The situation is further complicated by the tensions currently roiling the U.S.-South Korea alliance. Even as America steels itself for a nuclear North Korea, South Korea’s newly elected President Moon comes from the progressive Democratic Party of Korea, and appears to have a predilection for moving towards both North Korea and China. Just weeks after taking office, he froze the full deployment of the U.S.-provided Terminal High-Altitude Area Defense (THAAD) missile system. Days before Moon’s arrival in Washington, his special advisor on national security publicly hinted that U.S.-South Korean military exercises could be scaled back if Pyongyang made another promise to freeze its nuclear-weapons development, a move that no U.S. security analyst supports. Why, it surely will be asked, should America put not only its servicemen and women at risk, but its cities, for an ally that hedges on America’s security assistance?
Even if the Trump administration works out its differences with the Moon government, the repeated unwillingness under Democratic and Republican presidents alike to impose any serious costs on North Korea for its illicit activity and aggressions may ultimately wind up undermining U.S. credibility as much as walking away would. So far, the Trump administration has followed form, doing little in the face of Pyongyang’s multiple missile launches and worldwide cyberattacks in 2017. If Asian partners and adversaries believe that America’s behavior towards Pyongyang indicates that it is unwilling to risk a real confrontation, they may begin hedging against a perceived U.S. impotence.
Where the Korean peninsula is concerned, America’s national security policy stands at a crossroads. Its commitment to Seoul cannot simply be asserted as an ordinary foreign policy, or upheld solely on the account of tradition. Policymakers will have to convince the American public why they should be put at risk, if their involvement in the intra-Korean dispute is what puts them in that position.
As the naval (and soon-to-be nuclear) strategist Bernard Brodie said upon reading of the atomic bombing of Hiroshima, “everything I have written is obsolete.” The same may be said for America’s Korea policy.
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