The sad and bad reality is that in very many places in the world, this is exactly what happens. Children soldiers, children addicts, children prostitutes, children workers.
Now, I think most would agree that that is not what we want for our children, or any children, and that the protection from working exploitation and so on is a good thing indeed. But there is such a thing as going overboard with it, and seeing children as sort 'cut out of' the world we all live in, as little blank slates just waiting for us to write on, and nothing to do with the 'real' world.
Children are personalities with opinions, and they share our world for better or worse. We cannot protect them from it, nor in some cases should we, meaning they must learn the world, in as protected ways as can be managed, but they must not be kept apart from it or be seen as apart from it.