The article seems to cite public policy as the source of the difference. I don't think public policies are the root cause, but rather the underlying values of the culture that gave rise to them (as the article later seems to suggest). I'll bet that the U.S. end of that chart tends to be characterized by cultures that put individualism above all else, while the other end much less so.

Individualism is good; I'd never want the other extreme. I think Asian cultures subvert the individual to the group far too much. But the extreme individualism of the U.S. has led to an ever more selfish, narcissistic and cold society, where material gain and personal comfort trumps everything.