Last month’s summit between Russian Federation President Vladimir Putin and Democratic People’s Republic of Korea’s (DPRK or North Korea) leader Kim Jong Un was a clear illustration of how the global order is evolving and the increased connectivity of security affairs from region to region. The upgrading of relations between the two countries, culminating in the signing of a Comprehensive Strategic Partnership Treaty that included a mutual defense clause, formalized the cooperation that has been deepening between Russia and North Korea since Russia’s invasion of Ukraine. Evidence of illegal weapons transfers from DPRK to Russia has been leaked from government sources and found on the battlefields in Ukraine. That cooperation is expected to continue despite international condemnation, bolstering and prolonging Russia’s warfighting efforts. Concerns also run deep about the extent to which Russia might be willing to provide Pyongyang military technology assistance in return for or in response to South Korean actions regarding Ukraine, as well as how this backing may embolden North Korea’s military adventurism.

Just weeks later, the NATO Summit was held in Washington D.C. on July 9-11, marking the alliance’s 75th anniversary. Among the dozens of NATO country leaders and partners in attendance was Republic of Korea (ROK or South Korea) President Yoon Suk Yeol (also written as Yoon Suk-yeol). Despite his low approval ratings back home and calls for his impeachment, Yoon’s presence at NATO was a diplomatic success, both within and on the sidelines of the NATO summit.

While long-term support for Ukraine in its war against Russia was a major theme of the summit, specific language condemning the DPRK’s military assistance to Russia in the NATO Summit Declaration, the expansion of cooperation between NATO and its Indo-Pacific Partners—the “IPP” consisting of South Korea, Japan, Australia and New Zealand—and the strong condemnation of “illicit military cooperation” between Russia and North Korea in the IPP joint statement, were among several diplomatic wins Yoon can point to that show growing solidarity among like-minded partners on issues affecting peace and security on the Korean Peninsula.

That said, these NATO developments may not help Yoon in the polls back in South Korea, as growing integration on security matters between the Euro-Atlantic and Indo-Pacific regions brings its own risks. Among the expectations that come with greater cooperation is renewed pressure on Seoul to provide lethal military assistance directly to Ukraine, an action currently prohibited under South Korea’s Foreign Trade Act, rather than solely through third-party countries like the United States and Poland. While doing so would help enhance Ukraine’s warfighting efforts against Russia (which are supported by North Korean ammunition and missiles), Moscow has already threatened to expand military technology cooperation with North Korea if the ROK does provide lethal military assistance. Presumably, bolstered support from Moscow would help accelerate Pyongyang’s WMD development in ways that further jeopardize South Korea’s security situation. Yoon has stated that Russia should While Moscow disagrees with this kind of binary thinking, given its new treaty signed with Pyongyang, it seems Moscow has already made its choice, at least in the near term—the economic and security impact of which is yet to be seen.  

Moreover, China’s strong objections to both NATO’s expansion into Indo-Pacific affairs and its characterization of China’s relations with Russia could stall the recent momentum in both China-ROK bilateral and China-Japan-ROK trilateral cooperation as well. The hardening of Cold War-like alignments is not in Beijing’s interests, but neither is alienating its partners against growing NATO and Western creep into its backyard. Some in South Korea worry that these developments “could only push China, which is still hesitant to join the Russo-North Korean alliance, deeper into their arms.”

On the sidelines of the NATO summit, Presidents Biden and Yoon met to discuss bilateral matters, especially extended deterrence and alliance resolve against North Korea’s continued WMD development and deepening strategic cooperation with Russia. As a result, the two issued a joint statement announcing the signing of U.S.-ROK Guidelines for Nuclear Deterrence and Nuclear Operations on the Korean Peninsula. While few details of the document were publicly released, the guidelines reportedly include increasing the frequency of U.S. strategic assets to the peninsula to a “constant” level, and enhancing South Korea’s role in intelligence sharing, planning, training and operations.

The Biden-Yoon joint statement also highlighted progress on implementing the Washington Declaration, especially the significant contribution the establishment of the Nuclear Consultative Group (NCG) has made to upgrading extended deterrence cooperation and facilitating joint “nuclear and strategic planning,” as well as their commitment to make further progress in key areas such as conventional-nuclear integration, security protocols, crisis communication, and information sharing.

While the South Korean responses to Seoul’s deepening ties to NATO are mixed, the bilateral joint statement with the U.S. has been well-received. In particular, the statement’s explicit reference to U.S. nuclear capabilities as part of the full range of U.S. capabilities committed to the alliance appears to have elevated the sense of the U.S.-ROK becoming a nuclear alliance in Seoul. As much as this new language has intrigued the South Korean defense community, it is sure to be noticed in Pyongyang as well, although seen in a much different light. North Korea has yet to comment on either NATO or bilateral U.S.-ROK developments, but certainly, a response is coming, likely with equally strong nuclear rhetoric and demonstrations of power.