The US asylum program has shown epic fails in things like the taking in of the Persian Ayatolah (when maybe he should have been taken to guantanamo instead).
One of the things that always surprise me is the panic from deaths from terrorism, when the death toll from vehicle homicide and manslaughter is a lot higher and a lot more easily preventable.
Of course terrorism if not taken care of in time has the potential to multiply the casualties like a virus, but there are enough safe guards for it already.