Coronavirus restrictions that have limited his public appearances. Warning signals for his country's fragile economy, which has been battered by pandemic-related border closings and natural disasters. The impending departure of a US president who said he “fell in love” with him. As North Korean leader Kim Jong Un grapples with the toughest challenges of his nine-year rule, he's set to open a massive ruling Workers' Party congress next month to try to muster stronger public loyalty to him and lay out new economic and foreign policies.