With US foreign policy in flux, Japan and South Korea are finding common ground on trade, defense, and demographic challenges.

Washington’s increasing focus on Beijing is straining the decades-old alliance between South Korea and the United States.

South Korea's new president, Lee Jae Myung, will face a pivotal moment on Monday when he meets U.S. President Donald Trump in Washington for their first summit, as the countries' decades-old alliance strains to confront rapid geopolitical changes.