The Somalia-based Islamist insurgent group al-Shabaab has proved resilient, committing brazen terrorist attacks at home and abroad despite strategic setbacks in recent years.

The events of September 11, 2001, set in motion sweeping changes to U.S. intelligence and counterterrorism practices, launched two major wars, and altered Americans’ daily routines. This timeline tra…

The quadrennial U.S. presidential nominating conventions often focus on domestic themes. But they have at times been flavored by global economic concerns and national security threats, offering compe…