I'm very close to people who were saved from really horrible situations by state intervention. But then for them, foster care was hardly any better until they were adopted.
The state taking my kids is actually my worst parental nightmare--even beyond all the accidental and criminal bad things that could happen. I'm a very good parent (you'll have to take my word, I guess), but I'm not conventional. And I know all it takes sometimes is a little misunderstanding.