We have zero background information. Perhaps this guy is unstable and needs serious help. Did he show any sign of this before? If not, all the health care in the world would not have prevented it.
Scratch that, daily mandatory psychological visits for every single person in the country MAY have prevented this. A simmilar weekly regime could even have had a chance although a reduced one. But beyond the obvious statistical impossibilities of that idea, a policy like that would be admitting that you belive your populace to be insane unless proven sane which is only a little bit crazier than beliving everyone to be guilty until proven innocent.
Normally I would react to a confrontation in another country with the belief that it is a different culture and my idea of right and wrong does not neccesarily apply. If the basic facts presented so far are true though I can say confidently that this guy needs to not be alive anymore. When you place the value of your face above the life of another person you have commited a heinous and jealous act, no matter who you are. If your culture and your peers condone it, your people have problems, not just of the mental kind either. One day China is going to see a womens liberation movement that makes the one in the US look like a bake sale. There will be blood in the streets to repay this attitude to a womans life and worth. Of course, my opinion will never see the other side of the "Great Firewall".
But then it's not like this kind of thing doesn't happen in the US, or anywhere else in the world. Perhaps Douglas Adams was right, perhaps we all are decendants of a ship full of insane hair dressers and telephone sanitizers. That would explain a lot.