U.S. President Donald Trump made repeated invitations to meet North Korean leader Kim Jong Un as he prepared to visit South Korea this week, with officials in Seoul serving as his cheerleaders.

North Korea announced on Wednesday that it had launched sea-to-surface cruise missiles into its western waters.

"I got along great with Kim Jong Un. I liked him, he liked me," Trump told reporters on Monday — a reminder of his trademark tactic of flattering America’s adversaries, a style that infuriates critics...