The emergency of 9/11 is gone. Terrorism is no longer front of mind for most Americans. Active shooter atrocities and white supremacist violence have become more salient as domestic threats. And yet, domestic counterterrorism programs and policies are business as usual. This dissertation examines those policies and the connections between the national and local governments in the aftermath of the attacks of September 11, 2001. It explores national policies in policing, law enforcement and emergency preparedness and whether their cumulative effects constitute a new relationship between the federal, state, and local governments, a relationship that marks a turn in an important area of American government and constitutionalism. The project argues that the symptom of domestic warfare, a result of Bush-era War on Terror policies, is a systemic shift in the power balance in the American state and its federalist governmental structure. The concept of national security federalism is used as a general framework for gauging institutional change with the federal government’s push to centralize its prosecution of the War. The empirical focus is on military equipment exchange and intelligence production, primarily driven by the Department of Homeland Security. Evidence suggests that counterterrorism preparedness and intelligence capabilities are high in the cities and counties examined as a result. Based on in-depth interviews with a wide range of officials, security experts and community stakeholders, the study offers insights into how bureaucratic, elected and private sector actors pursue their work and how they conceive of themselves and their organizations vis a vis the mandates they are given, as well as the ones they adopt. The study finds that local institutions and actors have indeed changed how they operate, both ceding local power to the central government and taking for themselves some federal authorities at the expense of public accountability. It also finds very few cities attempting to reclaim sovereignty through privacy policy, unearthing interesting activities and combinations in the process.