Egypt's Hosni Mubarak Steps Down

Last night, President Hosni Mubarak spoke on Egyptian state television to say that he is not stepping down. Today, there are large crowds in Tahrir Square and across Egypt. Tarek Osman, author of Egypt on the Brink: From Nasser to Mubarak, joins us from Cairo to give us an update and describes how the role of the military has changed in the last few days.