The so-called Islamic State, or ISIS, has inspired young men and women all over the world to commit horrible atrocities in its name. How has the Islamic State surpassed al-Qaeda to become the most popular jihadist group on the planet? Its goal is not only to revive the Islamic empire but also usher in the End of Times - a final battle that will restore the Muslim community to its medieval glory days. And they will not stop until they achieve their mission.