When I initially read your reply I was going to suggest perhaps the homogeneity of Scandinavia might be a contributing factor. There is less of "us vs them" whereas in the UK and the US, there are many different groups of people, most of them are conquered people. In those cases, it's quite easy to see why there's such a sharp contrast. However, upon greater reflection, China also has very harsh sentences and a strong desire for revenge and China is pretty homogeneous so my initial theory doesn't make sense. One thing I wonder about is whether Scandinavia is the norm or the exception. To someone like me, a Chinese-American, harsh sentencing and "good vs evil" is the social norm, even if it's incredibly naive. I am now really curious as to what lead to the difference.