2 TWITTER, INC. v. TAAMNEH Opinion of the Court and to raise funds for terrorism. Defendants allegedly knew that ISIS was using their platforms but failed to stop it from doing so. Plaintiffs accordingly seek to hold Facebook, Twitter, and Google liable for the terrorist attack that allegedly injured them. We conclude, however, that plaintiffs’ allegations are insufficient to establish that these defendants aided and abetted ISIS in carrying out the relevant attack. I Plaintiffs’ case arises from a 2017 terrorist attack on the Reina nightclub in Istanbul, Turkey. The attack was carried out by Abdulkadir Masharipov on behalf of the Islamic State of Iraq and Syria (ISIS).1 Born in Uzbekistan, Masharipov had received military training with al Qaeda in Afghanistan in 2011 and eventually became affiliated with ISIS. In 2016, he was ordered by ISIS to travel to Turkey and launch an attack in Istanbul on New Year’s Eve. After planning and coordinating the attack with ISIS emir Abu Shuhada, Masharipov entered the Reina nightclub in the early hours of January 1, 2017, and fired over 120 rounds into a crowd of more than 700 people. In total, Masharipov killed 39 people and injured 69 others. The next day, ISIS released a statement claiming responsibility for the attack. Two weeks later, Masharipov was arrested in Istanbul after hiding out in ISIS safe houses. One of Masharipov’s victims was Nawras Alassaf, who was killed in the attack. Several members of Alassaf ’s family then brought the present lawsuit under §2333, alleging that they had been injured by the attack.2 Invoking —————— 1 In one form or another, ISIS has been designated a Foreign Terrorist Organization since 2004; it has also been known as the Islamic State of Iraq and the Levant, al Qaeda in Iraq, and the al-Zarqawi Network. 2 Plaintiffs appear to offer several theories as to the nature of their injury; because that question is not before us, we take no position as to any of those theories.