It has been two years since Boko Haram kidnapped nearly 300 schoolgirls from their dorm rooms in the Northern Nigerian town of Chibok. The missing girls captured the world's attention and launched the hashtag campaign #bringbackourgirls. Just this past week, "Nightline" Anchor Juju Chang travelled with Samantha Power, United States Ambassador to the United Nations, through three African countries, Chad, Cameroon and Nigeria, to report from the front lines in the battle against African jihad.Chang's report includes the latest on the search for the Chibok schoolgirls and thousands of others who have gone missing, as well as the military battle against the radical Islamist insurgency.