This exclusionary zoning, he argues, undermines diversity and opportunity. Kahlenberg explains that even in progressive states, restrictive zoning remains “fundamentally designed to separate people by income,” effectively creating walls that hinder mobility and economic equality. He points out, “If the cardinal sin of the right is racism, the cardinal sin of the left is elitism,” noting the contradiction in liberal communities that embrace social justice ideals while rejecting affordable housing policies.
Kahlenberg also emphasizes how tightly housing and education are intertwined, arguing that residential segregation drives educational inequality. He highlights research from Montgomery County, Maryland, where low-income students in economically integrated schools significantly outperformed peers in high-poverty schools despite added investments in the latter. Kahlenberg states, “Housing policy is school policy,” stressing the moral imperative to address zoning’s barriers to opportunity. As he puts it, exclusionary zoning does more than separate people—it blocks access to better schools, safer neighborhoods, and essential resources.