As host of CNN's "GPS," Fareed Zakaria dives into global issues with scholars, presidents, and the occasional celebrity. An optimist, Zakaria is nonetheless concerned about what he characterizes as a darkness in America brought on by people "who feel that they are not benefiting from all the changes in society." He talks with "Sunday Morning" contributor Kelefa Sanneh about his new book, "Age of Revolutions," in which he writes about how societies both embrace change and resist it.
