Those include a vast array of information-sharing programs, dozens of intelligence "fusion" centers formed by local, state and federal officials, and data-mining projects that involve probing mountains of telecommunications and commercial records for leads.
Details about the programs are contained in so-called "privacy impact assessments," although officials blacked out large portions of them pointing to security exemptions under federal open-government laws. The documents nonetheless offer hints about the scope of such initiatives.
Sections of the documents that are not redacted describe Pathfinder as an "integrated text search, retrieval, display and analytic tool suite used to analyze intelligence community message traffic," which would appear to fit the definition of data mining and includes personal information belonging to Americans.
Domestic spying has been a controversial issue since it was revealed five years ago that the National Security Agency eavesdropped on Americans and foreign nationals without warrants, under a secret order signed by President George W. Bush in 2002.