On the surface, President Yoon Suk Yeol’s visit to the US last week for the NATO summit may seem difficult to understand. An Asian leader attending a meeting of the trans-Atlantic defense alliance? The two regions are far apart physically with very little in common in terms of geopolitics. Did Yoon make the long 15-hour flight to Washington just to forget about the messy domestic politics? The answer should be no. In this age of ever-entangling, super-connected global security environment, what happens in Europe matters very much in Asia and vice versa. South Korea can no longer just sit and watch developments in Europe as if they are none of its business.

Just consider the ripple effect of the war in Ukraine on the Korean Peninsula. Russia and North Korea recently revitalized their military partnership in the wake of Pyongyang’s supply of munitions to Moscow for its war in Ukraine. In return, Russia is poised to provide satellite and missile technology to the North, heightening already high-security risks in Northeast Asia. For Europe, China’s geopolitical assertiveness and implicit support for Russia ring alarm bells loud and clear. In short, the two regions are increasingly intertwined geopolitically. Washington summed up the situation adequately. In a press release after the NATO summit, the White House stressed the “increasing connectivity between Euro-Atlantic and Indo-Pacific security,” adding “challenges in one region affect the other.”

That explains why top leaders of NATO’s four Indo-Pacific partners -- Japan, Australia, New Zealand and South Korea -- attended the summit celebrating NATO’s 75th anniversary. At the summit, the four countries pledged their continued support for Ukraine while condemning North Korea’s unlawful arms transfers to Russia. They also expressed their shared concerns on ever-growing military and economic ties between Pyongyang and Moscow as well as China’s support for Russia’s defense industrial base. The four Indo-Pacific nations inserted themselves deeply into Euro-Atlantic affairs. Concluding the summit, NATO Secretary-General Jens Stoltenberg declared “strong and deepening cooperation” between NATO and its Indo-Pacific partners.

That cooperation is perhaps strongest when it comes to South Korea. President Yoon’s participation in the NATO summit happened three years in a row and his liberal predecessor, Moon Jae-in, also pushed for greater ties with NATO. In 2022, South Korea opened its permanent mission at NATO’s Brussels headquarters. In the early 2010s, Seoul took part in NATO’s reconstruction programs in Afghanistan. The defense alliance also reciprocated. Last year, NATO offered South Korea the Individually Tailored Partnership Program, the most comprehensive agreement between the two since they opened dialogue in 2005. “South Korea has fallen in love with NATO,” said Ramon Pacheco Pardo, a professor of international relations at King’s College in London, in a column for the Center for Security, Diplomacy and Strategy in Brussels.

President Yoon in particular looks determined to strengthen the ties. In order to help NATO’s support for Ukraine, Seoul has indirectly supplied artillery shells and arms to Kyiv through US and Poland. The transactions, strongly urged by Washington, obviously strain Seoul’s relations with Moscow, but Yoon is not deterred. He now hints at supplying weapons directly to Ukraine in case Russia and North Korea further their military ties. Additionally, President Yoon pledged a $2.3 billion aid package to Ukraine this year, not a small amount given Russia’s repeated complaints and warnings.

Officially, Seoul’s advances to NATO are part of its efforts to pursue value-based diplomacy designed to uphold freedom and democracy. President Yoon’s vision of Korea as a Global Pivotal State requires assuming more responsibilities in global affairs, beyond Northeast Asia. Yet Seoul’s love affair with NATO is not purely platonic. South Korea could benefit commercially from arms sales to NATO member countries that are increasing their defense spending rapidly in the wake of the Ukraine War. Just last week, Romania agreed to buy nearly $1 billion worth of howitzers from Hanwha Aerospace. Last year, Korea exported $1.2 billion worth of fighters and other weapons to Poland, an 184 percent jump from the previous year. A number of other NATO members, including Norway, Finland and Estonia, have become major buyers of Korea’s weapons. It is ironic that the two Koreas, longtime recipients of weapons from major powers, have suddenly become new arms providers for two different security blocs of the world.

Yet South Korea’s growing ties with NATO should proceed with caution. As stated earlier, greater relations between the two will no doubt anger Russia and reinforce trilateral military cooperation among Moscow, Beijing and Pyongyang. Indeed, NATO’s eastward expansion since the end of the Cold War has caused a lot of security anxieties in the Kremlin, a partial reason for Russia’s invasion of Ukraine. Now that two more nations, Finland and Sweden, have become new NATO members, Russia’s concerns have grown even further. For that matter, Seoul’s cooperation with NATO needs to start in less confrontational and provocative areas.

Such areas include cyber defense, arms control, non-proliferation, new technologies and counter-terrorism where two parties can help each other with shared views and interests. For example, South Korea has participated in NATO’s annual cyber defense exercise since 2021. Also, Seoul took part in NATO’s Science for Peace and Security Program, focusing on emerging and disruptive technologies and defense against weapons of mass destruction. Such cooperation is expected to deepen as geopolitical risks of Asia and Europe are increasingly intermingled. Perhaps President Yoon should not shy away from joining NATO meetings no matter how long his flights are.

By Lee Byung-jong

Lee Byung-jong is a former Seoul correspondent for Newsweek, the Associated Press and Bloomberg News. He is a professor of international relations at Sookmyung Women’s University in Seoul. The views expressed here are the writer’s own. -- Ed.