Final answer:
The text doesn't directly answer Ghertner's question about Delhi, but it discusses urban renewal efforts in the U.S., which may include slum clearance for urbanization, addressing fiscal needs, and creating investment opportunities, often resulting in displacement without proper housing solutions.
Step-by-step explanation:
The main governmental imperatives that contributed to a renewed focus on the demolition of informal settlements in Delhi, as indicated by author A. Ghertner, are not explicitly provided in the provided text. However, the overall discourse on urban renewal during various periods historically has been characterized by the need to reinvigorate America's inner cities by endorsing gentrification, clearing slums, and facilitating new construction. This redevelopment often involved municipal governments adopting strategies to rebuild crumbling tax bases and address fiscal challenges through the clearance of undesirable dwellings under the guise of creating a 'clean slate' for investment and the development of public housing for the displaced.
It appears that the imperatives would likely be related to undertaking slum clearance to facilitate urbanization and modernization, addressing fiscal deficits of the governments, and attempting to create more attractive environments for investment. However, as highlighted in the excerpts, these efforts often resulted in the displacement of the underprivileged communities without adequate replacement housing, leading to the creation of new slums and exacerbating the original issues of housing scarcity and segregation.