Dr. Bill Warner how did Islam destroy the classical world

there were five major Patriarchs of the Roman Empire: Rome, Constantinople, Alexandria, Antioch, and Jerusalem. By 661, Alexandria, Antioch, and Jerusalem diminished by their permanent conquest by the Islamic Arabs. after hundreds of years of ongoing battles and unrest, Constantinople finally fell to the Ottomans muslims after a two-month siege on 29 May 1453. thus Rome was the fifth and the last surviving classical civilisation. if it had fallen to islam too, we all would be muslim or living under islam by