The campaign was first reported, on Saturday, by the British newspaper the Observer. However, sources familiar with the effort and pages of documents obtained by The New Yorker reveal that there is more to understand. Two of those sources told me on Sunday that the operation was carried out by Black Cube—a firm that was also employed by Harvey Weinstein and that offers its clients access to operatives from “Israel’s élite military and governmental intelligence units,” including the Mossad.