Why is the president of a country of 75 million so obsessed with pursuing a retired preacher who has been living in the U.S. since 1999? There are three main reasons for Erdogan’s obsession with Gulen: First, a desire to cover up massive and systemic corruption; second, the need for control over civic leaders and third, his need for a scapegoat to blame the country’s troubles and justify his authoritarian drive.