A recent rally in Seoul carried the sound of a rock festival — high-amp speakers throbbing with the K-pop hit “Gangnam Style” — if not the look of one. The crowd of mostly elderly people waved South Korean and American flags to the song’s revised refrain: “Anti-communist style!” When speaker after speaker revved up the crowd with pro-American, anti-communist chants, the crowd shouted, “Hooray for President Yoon Suk Yeol!”
Days later, when thousands of mostly younger protesters marched through the same city center, they shook handheld signs and chanted, “Out with…
