Israel held Hamas's full attack blueprint, a roughly 40-page document Israeli officials codenamed "Jericho Wall," more than a year before October 7. It described paragliders, drones, a multi-point breach of the fence, and an assault on the Gaza Division headquarters. It matched the real attack almost exactly.
Source: New York Times, Nov 30, 2023
Why it matters: Israel possessed a detailed map of the attack over a year in advance and intentionally chose to ignore it.