Gen. Gamal Abdel-Nasser, who overthrew King Farouk and established the Republic of Egypt, “often used art as a means to convey political messages and decisions to citizens, raise their morale and entrench their sense of belonging to the state.” (Among his collaborators: Umm Kulthum, then and now the Arab world’s most revered singer.) The country’s current president, Abdel Fattah al-Sisi, is using a similar approach.