Rescuers search through the rubble of the U.S. Marine barracks Oct. 23, 1983, in Beirut after a suicide truck bombing. The blast — the single deadliest attack on U.S. forces abroad since World War II — killed 241 American service members. The Supreme Court decided Congress can pass a law compensating the victims, and those of other attacks, using Iranian government funds. Jim Bourdier/AP hide caption

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Policemen search passengers at the entrance of the De Brouckere metro station in Brussels on March 24, two days after the terrorist attack on the city. PHILIPPE HUGUEN/AFP/Getty Images hide caption

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Investigation Continues As Brussels Recovers From Terror Attacks
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Salimata Sylla, a mother of three, visits Grand Bassam with her family to show she's not afraid of terrorists. On March 13, al-Qaida gunmen killed some 19 people at the beachfront town. Ofeibea Quist-Arcton/NPR hide caption

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A Day At The Beach Is A Way Of Saying 'We're Not Afraid' Of Terrorists
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A woman visits a memorial Nov. 16 near the Bataclan concert hall in Paris. The attack on multiple locations in Paris last fall left 130 dead. David Ramos/Getty Images hide caption

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Investigators in Belgium are asking the public's help in identifying this man who was seen at the Brussels airport before this morning's terrorist attack. Belgian Federal Police hide caption

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Terrorist Bombings Strike Brussels: What We Know
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The Bataclan concert hall in Paris was the scene of carnage during November's terrorist attack. The lifesaving actions that night by Didi, a security guard of North African descent, have only recently become known. Survivors say he may have helped save 400 to 500 people. Francois Guillot /AFP/Getty Images hide caption

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In France, A Quiet Hero Belatedly Comes To Light
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Investigators prepare to enter one of the residences where suspect Edward Archer lived in Yeadon, Pa. Archer is accused of ambushing a police officer in Philadelphia on Jan. 7. The FBI has said it is investigating the attack as a possible act of terrorism — inspired by ISIS. Matt Rourke/AP hide caption

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What Does It Mean If An Attack Is 'ISIS-Inspired'?
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Ambulances and police are seen at the blast site after an explosion in Istanbul's central Sultanahmet district. At least 10 people were killed and 15 wounded in a suicide bombing near tourists in central Istanbul's historic Sultanahmet district. Can Erok/Getty Images hide caption

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Explosion In Heart Of Istanbul's Tourist Area Kills At Least 10
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Members of the Los Angeles Police Department's elite Metropolitan Division participate in a simulation of a Paris-style coordinated attack. The team was tested on response time to converge on this site. Martin Kaste/NPR hide caption

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In Wake Of Attacks, U.S. Cities Step Up Terrorism Simulations
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After recent terrorist attacks, social media companies are under pressure to do more to stop messaging from terrorist groups. Patrick George/Ikon Images/Getty Images hide caption

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What Can — Or Should — Internet Companies Do To Fight Terrorism?
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