Well, that really raises questions about the kind of government Earth has as opposed to the way it's usually described.
Now, of course, that would apply to the children that they knew
about. And how resentful do you suppose that the families who escaped discovery would be of such treatment?
Maybe angry enough, after a long while, to detonate some things.
Cumberbatch as described his character as a terrorist. One might ask what sort of causes and conditions give rise to terrorists (particularly of the fictional variety). Certainly deep grievances borne for generations by a people who consider themselves oppressed and apart from the culture in power help.