Why al-Zawahiri’s death should focus attention on nuclear terrorism—foreign and domestic

The news that Ayman al-Zawahiri, the leader of the al-Qaeda terror group, was killed in a drone strike is not just a counterterrorism victory, but also a win for those seeking to prevent catastrophic nuclear terrorism. Al-Zawahiri’s role in the September 11, 2001 attack on the World Trade Center is well known, but his role in supporting al-Qaeda’s elaborate attempts to acquire a nuclear weapon is less well publicized.