Kim Jong Un is one of the few world leaders who has yet to congratulate — or even acknowledge — the president-elect North Korea has greeted the last two U.S. presidents with tests of missiles or nuclear bombs within weeks of taking office. And experts see the same happening with Joe Biden, whom the regime has called “a rabid dog.” Kim Jong Un is one of the few world leaders who has yet to congratulate — or even acknowledge — the president-elect, particularly after Chinese President Xi Jinping did so on Wednesday. While it’s not unusual for North Korea to stay silent on the results of U.S. elections, Kim held unprecedented meetings with President Donald Trump that broke the mold of relations between the long-time adversaries. Ties now are poised to revert to the frostier days of the Obama administration, when the U.S. deployed “strategic patience” to avoid rewarding North Korea for provocations — a policy that stayed in place after Kim took power in 2011. For North Kor...