That is exactly what our legal system does in many cases.
The act is inexcusable, but often the perp has no idea of wrongdoing.
Punishments are meant to teach a lesson and prevent crime. So how do you teach a lesson to someone who has no idea that they did anything wrong? No conception at all of the damage done.
I do not understand how you can make statements like that without any regard to motive and ability to discern right from wrong.
That is exactly what our legal system does in many cases.
Not really. Usually, they get locked up in mental hospitals until "cured." See: John Hinckley Jr.