Chinese President Xi Jinping's visit to North Korea coincides with the country's significant development in nuclear and conventional military capabilities, reportedly aided by Russian technology. These advancements could alter the regional power balance.

When Chinese President Xi Jinping arrived in Pyongyang on Monday, he was entering a country undergoing notable development in both its nuclear programme and conventional combat capacity. North Korea has been aided in these developments by Russian military technology and economic aid, which Pyongyang received in exchange for sending troops and equipment to support Moscow’s war in Ukraine. These advances could help Pyongyang threaten the balance of power against South Korea and the United...