The vulnerability of children is terrifying. Emotionally disturbed parents may abuse them. A sour economy, or warped economic priorities, may expose them to deprivation — child poverty is rampant in Japan, a recent UNICEF survey has shown.
Then there is education. It begins before school. It begins at birth. Infants are sponges, absorbing whatever is around them. If what's around them is good, good. If not, the damage is done, sometimes irreparably.
Small children by and large accept what their parents and teachers tell them. What defense have they against lies and nonsense? Some, if their immediate experience contradicts it; none otherwise. Parents, teachers, the ministry of education, can teach children anything they want, whatever suits their own or the state's purposes.