At noon on Monday, Xi Jinping arrived in Pyongyang for talks with North Korean leader Kim Jong-un, his first official visit since 2019. Analysts and news media outside China plumbed the newsworthy undercurrents, noting that China’s top leader was keen, in light of North Korea’s ever closer relations with Russia, to remind Kim who really calls the shots. Across the heavily militarized border in South Korea, some media turned in a search for subst…