The author is the senior columnist at the JoongAng Ilbo.

With negotiations with the Donald Trump administration settled at a "reciprocal" 15 percent tariff rate - the same as Japan - Korea has cleared one hurdle. Yet compared to the tradition, resources and persistence of diplomatic heavyweights like Japan and Taiwan, the country's overall engagement with the United States still appears unsteady. The collapse of a proposed special envoy mission to Washington amid internal political disputes illustrated the gap. It also reflected the absence of personal ties or direct channels to Trump's inner circle - a reminder that Korea has few diplomatic assets that could secure a meeting in the Oval Office.

Taiwan and Japan, both of which compete with Korea in exports to the United States, have long cultivated deep ties in Washington. Taiwan's Twin Oaks estate, once the Republic of China ambassador's residence, remains one of the capital's most grandiose properties. Even after Washington switched diplomatic recognition to Beijing, it allowed Taipei to retain the estate. By contrast, Korea handed over its prime embassy property in Myeong-dong to China. It is often said that almost every U.S. lawmaker has dined at Twin Oaks. At a recent national day celebration there, the chair of the House Foreign Affairs Committee declared that protecting Taiwan was central to U.S. security and economic interests. When then-Speaker of the House Nancy Pelosi visited Taipei despite Beijing's threats, her "ironclad" commitment to Taiwan was the product of years of cultivation. Successive Taiwanese governments kept Cui Tiankai in Washington for eight years to deepen channels, while Korea's ambassadors have changed with each administration.

Japan's approach draws on 120 years of U.S. diplomacy since the 1905 Katsura-Taft Agreement. In 1921, Tokyo's mayor gifted 3,000 cherry trees to Washington, which now line the Tidal Basin and form the backdrop for the National Cherry Blossom Festival. The event draws 1.5 million people, with Japanese corporations sponsoring food, drinks and cultural activities. Both Taiwan and Japan have worked relentlessly because the stakes are existential: Taiwan relies entirely on U.S. support for its survival, while Japan's rise after defeat depended on trade with the United States. Both frame themselves as key bastions of democracy against China and have impressed this on Washington for decades.

Korea, by contrast, spent 25 years after the Korean War as a top recipient of U.S. economic and military aid, losing some of that sense of urgency. Only when President Jimmy Carter pushed to withdraw U.S. troops over human rights abuses under Park Chung Hee did Seoul scramble to act - and then faced the "Koreagate" scandal. More recently, the lobbying controversy surrounding Sue Mi Terry during the Moon Jae-in administration limited access in Congress. Some on Capitol Hill reportedly avoid even casual meetings with Korean officials. Ironically, Trump's recent trade pressure has reminded Seoul of the weight - and urgency - of its U.S. ties.

Korea's chronic division is another weakness. A former senior U.S. diplomat noted that major Korean corporations rarely share information. Competition between Hanwha Ocean and HD Hyundai in U.S. shipbuilding, he said, has been so fierce that the U.S. is looking to exploit the rivalry. Unlike Japan or Taiwan, which present a united front among government, business and civil society, Korea spends heavily but works in silos. When bipartisan Korean delegations meet U.S. lawmakers, they often make conflicting requests and emerge with opposing interpretations - a pattern that has long been mocked in Washington. National unity is a diplomatic weapon.

Korea also struggles with soft-power engagement. For years, its diplomacy in Washington has focused on brief meetings and photo opportunities with senior figures. Japanese Minister Ryosei Akazawa reportedly endured the embarrassment of wearing a "MAGA" hat but t...