DHS was supposed to sensibly help coordinate existing departments with common goals hindered by bureaucratic divisions.
Instead we have something increasingly akin to a military which considers citizens at best suspicious and at worst presumed enemy combatants. Catholics, Evangelicals, and other predominant religious denominations are listed as indicators of potential terrorists. Anyone getting on an airplane with so much as a soda or can opener is presumed smuggling weapons. Anyone exhibiting self-sufficiency/survivalist tendencies is declared suspect. Vehicle checkpoints asking citizenship & business & destination are operated hundreds of miles inland. DHS employees are admonished to obey orders without question. Ammunition procurement[1] exceeding whole militaries is normalized. "Drone assassination" of citizens on home soil is declared (not legislated) lawful. Wholesale civilian monitoring (to wit NSA scandal) is common, and its consequences far from transparent now (save vague "a few terrorists were stopped"). Defacto national IDs are imposed/coerced (a la "Deine Papiere, bitte"). Wasn't long ago that every one of these points, and a whole lot more, were indicative of the worst oppressive governments; their recent commonality all a consequence of DHS.
This isn't just a result of a few vacancies at the top. This is systemic of the American leadership viewing the American people, and their historical values, being considered hostile opponents.
[1] - Yes, I'm aware of the alleged budgetary long-term purchasing theories. Even taking that into account, it's a whole lotta firepower intended against...who exactly?