The Trump administration has largely continued U.S. policies in Africa aimed at building economic ties, political stability, and health care, but it lacks a strategy for the continent’s looming geopo…

The collapse of the Cold War–era nuclear arms treaty signals trouble for U.S.-Russia relations, European security, and nonproliferation efforts.

The first summit between Joe Biden and Vladimir Putin eased some of the tension in the fraught U.S.-Russia relationship. It also laid bare the difficult path ahead to resolving differences on many is…