SEOUL—After an Olympics outreach that helped spark a thaw between South Korea and its nuclear-armed rival in the North, the newest tension-easing technique is K-pop diplomacy.
North Korean leader Kim Jong Un and his wife were in the audience Sunday as some of the biggest names in South Korean popular entertainment took to the stage in Pyongyang for the first of two planned concerts ahead of a summit between Mr. Kim and South Korea’s president.
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