Twenty-five years after al-Qaeda killed nearly 3,000 people in coordinated attacks on New York and Washington, a fifth of Americans still believe their own government was responsible — not because new evidence has emerged, but because trauma, institutional distrust, and the architecture of social media conspire to make false certainty feel more bearable than honest uncertainty. The persistence of these theories is less a story about 9/11 than about the enduring human need to impose order on catastrophe. What begins as a search for control can end in prejudice, isolation, and violence — a remin