combination ended the rule of the Gilded Age barons. As the city's demographics temporarily stabilized, labor unionization helped the working class gain new protections and middle-class affluence, the city's government and infrastructure underwent a dramatic overhaul under Fiorello La Guardia, and his controversial parks commissioner, Robert Moses, ended the blight of many tenement areas, expanded new parks, remade streets, and restricted and reorganized zoning controls. For a while, New York ranked as the most populous city in the world, overtaking London in 1925, which had reigned for a century. During the difficult years of the Great Depression, the reformer Fiorello La Guardia was elected as mayor, and Tammany Hall fell after eighty years of political dominance. Despite the effects of the Great Depression, some of the world's tallest skyscrapers were built during the 1930s. Art Deco architecture—such as the iconic Chrysler Building, Empire State Building, and 30 Rockefeller Plaza— came to define the city's skyline. The construction of the Rockefeller Center occurred in the 1930s and was the largest-ever private development project at the time. Both before and especially after World War II, vast areas of the city were also reshaped by the construction of bridges, parks and parkways coordinated by Robert Moses, the greatest proponent of automobile-centered modernist urbanism in America. Post–World War II: 1946–1977 Returning World War II veterans and immigrants from Europe created a postwar economic boom. Demands for new housing were aided by the G.I. Bill for veterans, stimulating the development of huge suburban tracts in eastern Queens and Nassau County. The city was extensively photographed during the post–war years by photographer Todd Webb. New York emerged from the war as the leading city of the world, with Wall Street leading the United States ascendancy. In 1951, the United Nations relocated from its first headquarters in Flushing Meadows Park, Queens, to the East Side of Manhattan. During the late 1960s, the views of real estate developer and city leader Robert Moses began to fall out of favor as the anti-urban renewal views of Jane Jacobs gained popularity. Citizen rebellion stopped a plan to construct an expressway through Lower Manhattan. After a short war boom, the Bronx declined from 1950 to 1985, going from predominantly moderate-income to mostly lower-income, with high rates of violent crime and poverty. The Bronx has experienced an economic and developmental resurgence starting in the late 1980s that continues into today. The transition