The State Department warns of potential anti-American violence following the U.S. killing of al-Qaida leader Ayman al-Zawahiri. Experts say his loss hurts the group, but doesn't erase the threat.

The U.S. targeted the top al-Qaida leader, showing it could track down and strike against a hard-to-find extremist figure even in a country where the U.S. has no military or diplomatic presence.

Zawahiri's death places al-Qaida in a precarious position, argues Colin P. Clarke of the Soufan Center. The question of succession will help shape al-Qaida now — and it may prove divisive.