For the purposes of this question, a CCTA is an [1] act of terrorism [2] involving multiple perpetrators working in concert [3] initiated with little or no warning [4] and employing one or more weapon systems (e.g., firearms, explosives, fire as a weapon, poison gas, vehicles as weapons) [5] that is intended to result in large numbers of casualties. For the purposes of this question, "terrorism" is as defined by federal law in 18 U.S.C. § 2331(1) & (5) (Cornell). Examples of CCTAs include the 2008 Mumbai attacks, 2013 Boston Marathon bombings, the Paris attacks in November 2015, and the 2015 San Bernardino, CA, office attack. Fatalities must occur during the question's open period to count, and whether an incident fulfills all of the criteria will be determined no later than 7 January 2026. The US includes the fifty states and the District of Columbia. The hijacking or bombing of an aircraft will count if the aircraft last took flight from the US or fatalities occur within the territory or airspace of the US, and an attack in the territorial waters of the US will count. A person who merely provisions those who perpetrate the attack will not be considered perpetrators for clause [2] in the definition.

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The question closed "No" with a closing date of 26 December 2025.

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