DHS looking at tracking travel of domestic extremists

Who determines which conservative or libertarian American Citizens are domestic extremists? Does one become a domestic extremist by expressing opposition to the current extra-constitutional activities of the federal government? What about personal opposition to members of the "junta" (e.g. Schumer or Pelosi)? How about participation in peaceful assemblies? What about appearing on TV shows such as Tucker Carlson Tonight, Hannity, or the Ingraham Angle? It seems that in many instances, our federal law enforcement and intelligence services relish in the possibility of putting down the rabble rousers and instigators. You know who they are, anyone who objects.