In the United States, urban form and design changed tremendously during the twentieth century. From the early twentieth century, a time when small-scale, highly diverse city blocks or what Douglas Rae called “urbanism” predominated, urban redevelopment came to be dominated by large-scale modernist superblocks, often promoted by federal policy. In the last two decades of the century, some urban designers argued for recapturing the physical qualities of the premodern city, while others argued that large-scale, autonomous city areas were both inevitable and ideal.