I don't believe this "disappearing" activity is as prominent as people are declaring.  Then again "disappearing" to me, is ending their life and permanently destroying the remains.  Deportation is not "disappearing" to me.

 I also don't think having an organization that enforces immigration and customs is against the US Constitution.  ICE can break laws, be overall hostile/manipulative and not violate the Constitution, but it sure sounds better to claim it that way.  Kind of how COVID mask requirements were "Unconstitutional", and speed limits, and helmet laws, and State driver licenses.