Anti-government protesters in Cairo's Tahrir Square react to a televised statement on Feb. 10, 2011, by Egyptian President Hosni Mubarak, who stepped down the following day. His departure and that of Tunisia's Zine el-Abidine Ben Ali have some seeing the twilight of U.S. influence in the Middle East and others seeing new opportunities. (Associated Press)

Anti-government protesters in Cairo's Tahrir Square react to a televised statement on Feb. 10, 2011, by Egyptian President Hosni Mubarak, who stepped down the following day. His departure and that of Tunisia's Zine el-Abidine Ben Ali have some seeing the twilight of U.S. influence in the Middle East and others seeing new opportunities. (Associated Press)