North Korean leader Kim Jong Un said the United States is his nuclear-armed nation’s “biggest enemy”, state media reported Saturday, as he threw down the diplomatic gauntlet to the incoming administration of Joe Biden. The declaration comes less than two weeks ahead of the new US president’s inauguration and after a tumultuous relationship between Kim and the outgoing leader Donald Trump. Kim and Trump first engaged in a war of words and mutual threats, before an extraordinary diplomatic bromance that featured headline-grabbing summits and declarations of love by the US president. But little substantive progress was made, with the process