The project can be seen as a metaphor for modern Berlin, according to this piece from The Wall Street Journal.
"...[A] vast laboratory for cultural production and modern urban planning, largely built on the debris of European culture.
Dubbed by architect Norman Foster as "the mother of all airports," Tempelhof was one of the oldest in Europe, and before it closed to air traffic in 2008 it served as a testing ground for the Wright Brothers, the nerve command of the Nazi Luftwaffe and the base of the U.S.-led Berlin Airlift, West Berlin's lifeline during the Soviet-led blockade of 1948-49. The name Tempelhof comes from the Knights Templar, who encamped here in the 13th century. Later the field served as the Prussian Army's exercise ground.
Everyone in Berlin (and beyond) seemed to have an idea of what to do with the 950-acre, eye-shaped hole left in the city by the airport's closure. Suggestions ranged from luxury condos to an ice-skating rink. It was rumored the U.S. businessman Ronald Lauder had expressed interest in developing the field. In the summer of 2009, thousands of demonstrators tried to occupy the airfield to protest the rumored privatization of the public space, but the crowds were diverted along the airport's northern border and few arrests were made."