The swift development of effective vaccines against COVID-19 was an unprecedented scientific achievement. But production challenges, vaccine nationalism, and new variants have all presented hurdles.

Recent killings by U.S. officers have sparked widespread calls for police reform and an end to systemic racism. Here’s how U.S. policing compares with other countries’ approaches.

Violence continues to rage more than a decade after the Mexican government launched a war against drug cartels.

The G20 summit comes amid tensions over trade, climate, and refugee policy and increased uncertainty over the U.S. commitment to multilateral institutions.

U.S. space exploration inspired a generation of students and innovators, but NASA’s role has diminished, and the number of global space competitors is growing.