“For many Americans, the term mass surveillance evokes the Department of Homeland Security, which was founded after the 9/11 terrorist attacks. This national agency, which forms part of a federal intelligence apparatus of more than 20 agencies focused on surveillance, has played a key role in mass surveillance since 2001, especially of Muslim Americans.
But it has local help in the form of police units known as fusion centers [including in Washington] (https://www.dhs.gov/fusion-centers). These units feed identification information and physical evidence such as video footage to federal agencies such as the FBI and CIA [as well as DHS and ICE] according to a 2023 whistleblower report from Rutgers Law School.