Richard M. Daley, son of Richard J. Daley, became mayor in 1989, and was repeatedly reelected until he declined to seek re-election in 2011. He sparked debate by demolishing many of the city's vast public housing projects, which had deteriorated and were holding too many poor and dysfunctional families. Concepts for new affordable and public housing have changed to include many new features to make them more viable: smaller scale, environmental designs for public safety, mixed-rate housing, etc. New projects during Daley's administration have been designed to be environmentally sound, more accessible and better for their occupants. In 2011, Rahm Emanuel was elected mayor of Chicago. Chicago earned the title of "City of the Year" in 2008 from GQ for contributions in architecture and literature, its world of politics, and the downtown's starring role in the Batman movie The Dark Knight. The city was rated by Moody's as having the most balanced economy in the United States due to its high level of diversification. Flag Four historical events are commemorated by the four red stars on Chicago's flag: The United States' Fort Dearborn, established at the mouth of the Chicago River in 1803; the Great Chicago Fire of 1871, which destroyed much of the city; the World Columbian Exposition of 1893, by which Chicago celebrated its recovery from the fire; and the Century of Progress World's Fair of 1933–1934, which celebrated the city's centennial. The flag's two blue stripes symbolize the north and south branches of the Chicago River, which flows through the city's downtown. The three white stripes represent the North, West and South sides of the city, Lake Michigan being the east side. Major disasters The most famous and serious disaster was the Great Chicago Fire of 1871. On December 30, 1903, the "absolutely fireproof", five-week-old Iroquois Theater was engulfed by fire. The fire lasted less than thirty minutes; 602 people died as a result of being burned, asphyxiated, or trampled. The S.S. Eastland was a cruise ship based in Chicago and used for tours. On July 24, 1915—a calm, sunny day—the ship was taking on passengers when it rolled over while tied to a dock in the Chicago River. A total of 844 passengers and crew were killed. An investigation found that the Eastland had become too heavy with rescue gear that had been ordered by Congress in the wake of the Titanic disaster. On December 1,