The Department of Homeland Security anti-terrorism activities have created a totalitarian system where people can be arrested and held without due process. It violates the rights outlined in the US constitution, and takes the country back to the days of McCarthy-ism and the imprisonment of Japanese-American citizens during WW2.
America is a "melting pot" country - our strength is the variety of our heritages and experiences. DHS creates fear and hostility against anyone who doesn't "look like us" or "sound like us", when "us" were just like "them" a generation or two before.
The cost over and above the departments that DHS absorbed has increased by $25 Billion or more since it was created. DHS has effectively created an internal "spy agency" that has no financial or oversight limits.