@Leemon
It's a difference in culture. In japan, they don't have the culture of shaming traditional families like we have on the West, so a man wanting to work to sustain his family and the woman wanting to become a housewife are not only encouraged, but well seen in the society.
On the West, on the other hand, if you're not both working and letting the government raise your child, so they can brainwash your kids into becoming tools for the socialist empire, you're sexist, racist, homophobic, islamophobic, and whatever other bullshit label they can think of to put on you.
"There is a law in Japan which say that women can't work or it's just sexism ?"
Women are more than free to work if they want, the problem is that the West has become so sexist, you perceive individual choice as proof of inherit sexism.