(IANAL) To make that really work, you need to collate data from different databases located in different sovereignties. If somebody is on an American sanctions

(IANAL) To make that really work, you need to collate data from different databases located in different sovereignties. If somebody is on an American sanctions list, then Facebook USA making an account for that person on a database located on American soil violates the sanctions. That American citizens can't see the relevant account's data is irrelevant; if anything, it could actually amount to obstruction of justice if American investigators have a warrant to see the relevant data on an American server and it does not appear in the investigator's UI despite the warrant. The way to solve that is to have different legal entities own different sets of data that exist under different sovereignties and then draw upon the data from each sovereignty through established (although potentially entirely private to Facebook and its foreign subsidiaries operating the foreign servers) protocols.