In the 2015 attacks, 130 people were killed, including at the Bataclan concert hall. France is still wrestling with how to remember the deadliest attack on its soil in modern history and how to live with it.
The weekend bombing of a Palm Springs, Calif., fertility clinic has cast a fresh spotlight on a 19th century philosophy linked to Russian revolutionaries. What does "nihilism" mean?
Some researchers say these recent attacks are examples of "nonideological" terrorism — the result of several antisocial, decentralized, online networks coming together.
Bourbon Street re-opened in New Orleans Thursday afternoon, more than 24 hours after Wednesday morning's attack by a Texas man driving a Ford pickup truck plowed into a crowd of New Year's revelers.
Authorities say the driver drove around a barricade and plowed through a crowd along Bourbon Street, the city's iconic stretch of bars and hotels near the French Quarter.
The Justice Department said the man was inspired by the Islamic State militant organization and was plotting an Election Day attack targeting large crowds in the U.S.
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.
In 2001, as the nation mourned those killed on 9/11, the government tried to find its footing to prevent more terrorist attacks. In the 20 years since, the nature of those threats has evolved.
Richard Guadagno died when United Airlines Flight 93 crashed on 9/11. His memory is scattered through his sister Lori's house in items that continue a conversation between the siblings 20 years later.
Presidents' reactions have consistently combined outrage with promises of revenge. The language is remarkably similar. But there has been far less consistency in the delivery of actual retaliation.