Drawing on thousands of al Qaeda documents seized in the 2011 raid that killed Osama bin Laden, Nelly Lahoud reveals that the other side struggled with the same question. The 9/11 attacks were meant, in bin Laden’s words, to “destroy the myth of American invincibility.” Ultimately, Lahoud writes, “bin Laden did change the world—just not in the ways that he wanted.”

Bin Laden’s worldview and the thinking behind the 9/11 attack are laid bare in a trove of internal communications that were recovered in May 2011, when U.S. special operations forces killed bin Laden during a raid on the compound in the Pakistani city of Abbottabad where he had spent his final years hiding. In the years that followed, the U.S. government declassified some of the documents, but the bulk of them remained under the exclusive purview of the intelligence community. In November 2017, the CIA declassified an additional 470,000 digital files, including audio, images, videos, and text. With the help of two research assistants, I pored over 96,000 of those files, including nearly 6,000 pages of Arabic text that form a record of al Qaeda’s internal communications between 2000 and 2011, which I have spent the past three years analyzing. These documents consist of bin Laden’s notes, his correspondence with associates, letters written by members of his family, and a particularly revealing 220-page handwritten notebook containing transcripts of discussions between members of bin Laden’s immediate family that took place in the compound during the last two months of his life. The documents provide an unparalleled glimpse into bin Laden’s mind and offer a portrait of the U.S. “war on terror” as it was seen through the eyes of its chief target.