"The people of the world can live together in peace," Obama said at Cairo University. "We know that is God's vision. Now that must be our work here on Earth."
In Obama's view -- although he did point to the threat of terrorist groups such as al-Qaida -- the primary source of recent historical tensions between the West and the Islamic world has been the colonialism and cultural imperialism of the West.
"The relationship between Islam and the West includes centuries of coexistence and cooperation, but also conflict and religious wars," Obama said in Cairo. "More recently, tension has been fed by colonialism that denied rights and opportunities to many Muslims, and a Cold War in which Muslim-majority countries were too often treated as proxies without regard to their own aspirations. Moreover, the sweeping change brought by modernity and globalization led many Muslims to view the West as hostile to the traditions of Islam."
In February 2011, less than two years after Obama's Cairo lecture on world peace, popular protests forced the pro-American Mubarak to resign.
Peace was not at hand for Egypt's 10-percent Christian minority.
"The government failed to protect Christians and their property effectively when they were attacked in Dahshour, Alexandria, and Rafah, and often failed to investigate and prosecute crimes against Christians and other religious minorities," the State Department said in its 2012 report on religious freedom in Egypt.
In June 2012, Mohammed Morsi, a member of the fundamentalist Muslim Brotherhood, won Egypt's presidency with 51.7 percent of the vote. He was not an evangelist for religious comity.
"On October 19, President Morsi said 'Amen' during televised prayers in Mansour after an imam stated, 'Oh Allah ... grant us victory over the infidels. Oh Allah, destroy the Jews and their supporters,'" the State Department reported. "This is a common prayer in Egyptian mosques and came in a litany of other prayers."
On July 3, 2013, the Egyptian military overthrew Morsi. But that did not heal Egypt.
"In 2013, violent sectarian attacks, targeting primarily Copts, occurred both during and after Morsi's tenure," said the 2014 report of the U.S. Commission on International Religious Freedom.