A. Bruce Bielaski, the Chief of the Bureau since 1912, left as the Great War came to its close. Thousands of informants and hundreds of agents subsequently left the agency and took with them the institutional knowledge and experience gained during the war. A new set of leaders searched for a new mission for the Bureau. Communist Russia, strengthened as a result of Germany’s defeat, now sought to export the Marxist-Leninist Revolution to America. The red scare gave the Bureau a new purpose. Yet, corruption and incompetence of Chiefs William J. Flynn and William J. Burns shaped the organization until J. Edgar Hoover took charge in 1924.