US President Donald Trump (3L), US First lady Melania Trump (2L), Saudi Arabia's King Salman bin Abdulaziz al-Saud (C), and Egypt's President Abdel Fattah el-Sisi (3R) pose for a group photo with other leaders of the Muslim world during the inauguration of the Global Center for Combating Extremist Ideology in Riyadh on May 21, 2017. / AFP PHOTO / MANDEL NGAN        (Photo credit should read MANDEL NGAN/AFP/Getty Images)