Vaccines are a major public health success story, but the COVID-19 pandemic underscores the many challenges involved in getting a vaccine to everyone who needs it.

Ayman al-Zawahiri leaves behind a robust network of strategically aligned but tactically independent al-Qaeda affiliates operating in Africa, Asia, and the Middle East.

The federal agency tasked with weather forecasting and research has played a growing role in climate policy, but also faced controversy during the Trump administration. What does NOAA do?

Russia’s extraordinary show of force in and around Ukraine underscores the military imbalance between the two countries. 

A look at the post-9/11 war powers law that the Trump administration could use to justify conflict with Iran.