Does the killing of al-Zawahiri make Americans safer? It's complicated
3 things the strike on al-Zawahiri tell us about the U.S. counterterrorism strategy
Bin Laden was the face of al-Qaida, but Ayman al-Zawahiri was its hate-filled heart
The U.S. has killed top al-Qaida leader and key 9/11 plotter, Ayman al-Zawahiri