Mr. Kim, or: How Korea Learned to Love the Bomb

South Korea and Japan—two countries that, like Germany, were able to grow into economic powerhouses within the postwar order under the nuclear umbrella of the Pax Americana—have traditionally considered the question of nuclear armament off-limits. While the issue has occasionally been raised by nationalists, and in Korea even backed at times by more concrete steps, the prevailing principle has always been: We trust Washington! Japan, with its pacifist constitution, committed itself in 1967 to the Three Non-Nuclear Principles (based on a parliamentary resolution, not a law): no possession, no production, and no stationing of nuclear weapons. At least the last of these is something that some experts would be quite willing to see reconsidered.

Crumbling Security Assurances from the United States

American security assurances are no longer what they once might have been. Even in better times, the nuclear dilemma was already clear: nuclear weapons deployed by a foreign state to protect another’s territory cannot provide the same level of security as one’s own arsenal. Would a U.S. president, in a real crisis, truly risk a nuclear strike on Chicago in order to retaliate for an attack on Seoul?

In a Trump-era world, where the U.S. president seems to view alliances at best as bidding clubs for the highest American profit, and at worst as burdensome constraints on U.S. power, the question of whether it might be necessary to develop one’s own nuclear weapons has once again returned to the agenda in East Asia—just as it has in Europe. 

Unlike South Korea, Japan is even considered a nuclear threshold state—that is, a country possessing what is known as nuclear latency: the knowledge and technology that would, at any time, make it possible to build a weapon.

Both countries are strong advocates and exporters of civilian nuclear technology. Unlike South Korea, however, Japan is even considered a nuclear threshold state—a country that, in theory, possesses what is known as nuclear latency: the knowledge and technology to build a weapon at any time. This includes the capability to enrich uranium to weapons-grade levels. South Korea, by contrast, is bound by a so‑called bilateral “123 Agreement” with the United States, which contractually prohibits it from enriching uranium above 20 percent or reprocessing plutonium without U.S. consent. This unequal treatment compared to Japan has long been a source of grievance among South Korean conservatives.

Achieving parity with Japan would not violate the Nuclear Non‑Proliferation Treaty (NPT) and would allow Seoul—at a time when American security guarantees have grown shaky—to keep an additional form of deterrence in reserve. Japan’s so‑called “breakout time” is estimated at only a few months, while South Korea’s is believed to be two to three years. At the same time, however, the risk would rise that Russia or North Korea, in an attempt to stop South Korea from developing the bomb, might be willing to launch a preventive strike similar to the one carried out against Iran.

International Isolation as the Price of Nuclear Armament?

While in Japan—due in large part to the experiences of Hiroshima and Nagasaki—a majority of the population rejects any form of nuclear armament, polls in South Korea regularly show up to 75 percent of respondents supporting such an option. Although the topic frequently arises in public debates, it has so far been clear that South Korea, which is militarily even more dependent on the United States than Germany, would not take the step toward developing nuclear weapons. Experts believe that the high public approval mainly stems from a misunderstanding of the consequences: South Korea’s withdrawal from the NPT would instantly turn the country into a pariah, likely leading to sanctions from the U.S. and the EU. At the same time, the vital defense alliance with the United States would suffer serious damage.

If the public were made aware of these consequences—that the price of nuclear armament would be international isolation—most people, scientists believe, would decide against it. However, in an era of Trump-style hardball diplomacy, the automatic nature of these consequences can no longer be taken for granted. Washington might even have a mid-term interest in increasing the nuclear deterrence of both allies vis-à-vis China.

Unlike in Europe, the United States so far appears to have no increased interest in this—regardless of the nuclear question—in either Korea or Japan.

For Seoul, there is also the fact that the United States leaves little doubt that, in the event of a regional conflict with China, containing North Korea will not be the top priority for U.S. forces stationed in Korea (USFK). For Seoul, whose new government is still trying to navigate a course between the U.S. and China, North Korea remains the primary threat. Perhaps it would be wise, then, to gain more autonomy in defense matters?

Unlike in Europe, the U.S. so far appears to have no increased interest in this—regardless of the nuclear question—in either Korea or Japan. Although South Korea’s newly elected President Lee has promised to pursue greater autonomy for the Korean military from the U.S., operational control (OPCON) over Korean troops still rests with the American commander in Korea in the event of a conflict. How realistic the long-held autonomy aspirations of the Korean left are remains uncertain.

In recent weeks, however, the new Korean government has repeatedly linked this issue with the question of greater nuclear freedom, including, among other things, the potential use of uranium for building nuclear-powered submarines. Given the global ties of the South Korean economy with the U.S. and the EU—and as the world’s second most important semiconductor manufacturer after Taiwan—the question also arises how severe potential sanctions might actually be.

For Pyongyang, the lessons from the attack on Iran are likely clear—especially after American and Israeli voices briefly linked the strikes to a possible (though unrealistic) regime change: only nuclear armament protects a regime from being toppled by American intervention. On one hand, the U.S. made clear through the strike on Iran that it is willing to carry out military attacks if necessary. On the other hand, it remains uncertain whether even the massive U.S. assault was sufficient to set back Iran’s nuclear program by more than a few months. The North Korean underground facilities—which the Iranians are said to have helped design—would thus have little to fear in the event of an escalation.

Nuclear Negotiations with North Korea: Trump’s Next Move?

While Pyongyang can relatively calmly sit back when it comes to nuclear weapons, the nervousness in Seoul is greater. There are fears that Trump’s craving for attention—driving him to pursue a Nobel Peace Prize now that peace in Ukraine seems unrealistic and an agreement with Iran is at least difficult to achieve—might lead him to negotiations with North Korea. The regime, represented by Kim Jong Un’s sister, has recently signaled openness to this. However, the condition would be that the U.S. recognizes North Korea as a nuclear power.

Negotiations during Trump’s last term failed both because of the American demand for the regime’s complete denuclearization and the expected resistance in Congress. This time, Trump reportedly has better control over Congress, but it remains unclear whether the U.S. would be willing to make such a deal—especially if it might make Trump appear weak. Such a deal would likely be much harder to achieve now than during Trump’s first term. The pressure on the regime has significantly eased thanks to closer cooperation with Moscow—so what can Washington offer Mr. Kim that the regime cannot also get from its renewed friends in Russia?

For the United States, however, the question would remain how North Korea will behave on other fronts.

Still, in South Korea, there is concern that Trump’s “America First” approach might make him willing to compromise. He may not be as worried about North Korea possessing nuclear weapons capable of threatening South Korea as he is about whether North Korea has delivery systems that can reach the United States. Trump could therefore consider it a sufficient negotiating success if the North simply gives up its intercontinental missiles. North Korea’s nuclear weapons would then primarily pose a problem for Seoul and Tokyo, even though they could still threaten U.S. bases in the region.

For the U.S., however, the question would remain how North Korea behaves on other fronts. The continued deployment of troops to Russia may not matter much to Trump, but as a potential escalation wildcard in a regional conflict with China, a post-deal North Korea would still be a risk for the U.S.

Discussions in South Korea and Japan will therefore continue in one form or another. The parallels to the EU are unmistakable. On the one hand, there is a need for greater strategic independence; on the other, complete independence from the U.S.—especially in terms of nuclear armament, but also conventional forces—remains an illusion. The only makeshift alternatives are strengthening regional cooperation (for example, between South Korea and Japan, but also with Australia) and reinforcing the international order in partnership with Europeans. Both strategies still leave significant room for improvement.