Some children are placed for adoption because the courts claim that the mother agrees to this when she doesn't. Others are in care because of mums political views (going on an EDL march for example). I really don't think this is other than state sponsored child stealing.
Obviously we need a child protection system but it doesn't protect children from being starved to death or indeed from being raped whilst in the care of the local authority. What it does do is get children adopted.