However, U.S. officials had to take greater notice just days later when Won Yoo‐Cheol stated that the time had come for his country to acquire its own nuclear weapons. Implicitly referring to the nuclear shield that the United States provides the ROK as part of the bilateral security alliance, Won emphasized: “We cannot borrow an umbrella from a neighbor every time it rains. We need to have a raincoat and wear it ourselves.”
Won Yoo‐Cheol is not some obscure figure. He is the floor leader for the governing party in South Korea’s parliament. His endorsement of the nuclear option indicates just how seriously it has begun to penetrate the ranks of South Korea’s elite.
As yet, President Park Geun‐Hye has not shown any sympathy for that position. But two points should be kept in mind. First, her popularity and that of her party has been dropping in the aftermath of North Korea’s most recent provocations. The temptation to embrace popular countermeasures will rise. Second, her father, Park Chung‐Hee, who ruled South Korea in the 1960s and 1970s openly flirted with acquiring an independent nuclear arsenal. Only intense U.S. pressure, combined with more tangible U.S. security assurances dissuaded him from proceeding. One has to wonder whether his views influenced his daughter.
Washington is as adamantly opposed to a South Korean nuclear deterrent now as it was four decades ago. U.S. officials fear that such a development would eliminate even the fading chance that North Korea might relinquish its nuclear program. More broadly, American policymakers worry that Japan would follow suit and become a nuclear‐weapons state, and Northeast Asia would then experience a full‐blown, highly destabilizing nuclear arms race. Acquisition of independent deterrents would also mean the dilution of Washington’s dominance over its East Asian allies.
U.S. leaders have sought to avoid that outcome by firmly placing both South Korea and Japan under the American strategic nuclear umbrella. The growing sentiment in the ROK in favor of a national deterrent suggests that the credibility of the U.S. commitment has faded. Washington now seeks to boost that credibility by deploying a sophisticated theater missile defense system to protect the allies from attack.
The odds are still against the emergence of a nuclear‐armed South Korea, but that outcome is not nearly as improbable as it once seemed. And if it does occur, it is a complete game changer. It is bizarre that the United States is still expected to treat the ROK, which has twice the population and an economy 40 times the size of North Korea’s, as a helpless protectorate. But it would be much more so to risk getting into the middle of a potential conflict between two nuclear‐armed Korean states. South Korea’s acquisition of a nuclear deterrent should strengthen the case, and hasten the day, for a U.S. military withdrawal from the Peninsula.
For China, the dilemma could be more acute. North Korea is a long‐standing ally, but South Korea is an increasingly important economic partner. The only thing worse for China than a war on the Korean Peninsula would be a nuclear war on the Peninsula. The prospect of a nuclear‐armed South Korea should create a maximum incentive on Beijing to pressure Pyongyang to cease its nuclear tests and other destabilizing actions. In addition to the growing likelihood that South Korea may respond by barging into the global nuclear weapons club, Japan might also do so, and Chinese leaders clearly do not want that outcome.
At a minimum, recent developments suggest that the patience of the South Korean people and some members of the political elite is wearing thin. South Korea has begun to flirt with the nuclear option, and if North Korea’s nuclear provocations are not curbed decisively, that flirtation may turn into a full‐blown relationship.