And unlike the NSA, the DHS has the ability to arrest people.
Via Daily Caller:
Domestic spying capabilities used by the National Security Agency to collect massive amounts of data on American citizens could soon be available to the Department of Homeland Security — a bureaucracy with the power to arrest citizens that is not subject to limitations imposed on the NSA.
Unlike the DHS, the NSA is an intelligence agency, not a domestic law enforcement agency. It cannot arrest those suspected of wrongdoing. That power of the federal government lies with agencies under the jurisdiction of the Justice Department, the Treasury, Homeland Security and other law enforcement agencies.
The NSA and DHS have waged a long Capitol Hill turf war over cybersecurity. Bills such as the Cyber Intelligence Sharing and Protection Act and the Cybersecurity Act of 2012 have sought to clearly define the relationship between the two agencies, but struggled to get off the ground.