The Meaning of the Black Muslim Flag

I was reading a story on Fox News today about Egyptian President Morsi and read something disturbing in its ignorance or its intent to deceive readers. The story, which is from the Associated Press, states:

In the interview, Morsi dismissed criticism that he responded too slowly when protesters managed to scale the walls of the heavily fortified U.S. Embassy in Cairo on Sept. 11. The demonstrators replaced the American flag with a banner carrying the Islamic declaration of faith.  

CBS reported at the time the following:

Dozens of protesters scaled the embassy walls, went into the courtyard and took down the flag from a pole. They brought it back to the crowd outside, which tried to burn it, but failing that, tore it apart. The protesters on the wall then raised on the flagpole a black flag with the Muslim declaration of faith on it, "There is no god but God [sic] and Muhammad is his prophet."

Here's a photo:

The black flag has special significance in Islam. As Joel Richardson explains in his book, Antichrist: Islam's Awaited Messiah:

In Islam there are two flags. One is white and one is black. Written across both flags in Arabic are the words, "There is no God but Allah and Muhammad is his Messenger." The white flag is called Al-Liwaa and serves as the sign for the leader of the Muslim army and is the flag of the Islamic State. The black flag is called Ar-Raya and is used by the Muslim army. It is also called the flag of jihad, and is carried into battle. One flag is governmental and the other is a military flag. 

 * * * 

Islamic tradition pictures the Mahdi [the Islamic messiah] as joining with teh army of Muslim warriors carrying black flags. The Madhi will then lead this army to Israel and re-conquer it for Islam. The Jews will be slaughtered until very few remain and Jerusalem will become the location of the Mahdi's rule over the Earth.

(pp. 45-46).