There are a few different forms of 'western culture'. They don't all fit together and they don't all apply to the same things. I'll try to identify some of them to get things going:
a) Religious: Christianity in short. Any deviations exclude you from 'Western' in the religious sense. Narrow definition of 'western' here but it gets included into the mix.
b) Cultural: This is a big one and breaks down to subfactors. It deals with language, arts, literature, cinema, music, dance, architecture and so on. In this case Western culture reaches all those who, for example, watch a Hollywood movie. They are consuming western culture because Hollywood cinema is informed by western philosophy, contains the English language, is possibly informed by a particular book in that language and typically has US or UK music in it. But the English language is not a determining factor, as any French man will tell you. The easiest way of summing up this category is by looking at the ideas and philosophies behind such culture products.
c) Economic: This basically means capitalist, not necessarily with free trading policies. What so often gets confused as 'western culture' (b) is basically an economic model and nothing to do with culture or religion. China is a good example here and so is Russia. The West in economic terms is what places the culturally different Japanese nation in the same basket as that of say The Netherlands. When you see an African drinking Coca-cola whilst wearing a Paul Smith suit he hasn't 'gone western', he's just a part of the global economic system and benefiting from the goods flowing through it.
d) Political: Typically democracy, but shades of conservatives, liberalism etc all get included as long as it remains representative. This is quite a dated definition imo and ended when the Cold War did. There is no monopoly on the development of democracy so it's not accurate to call it western.
e) Ethnic: WASPs in general but again it gets sticky as you move to the peripheries. Is a Bulgarian or Romanian as Western as a Frenchman or an Englishman? How does a Russian compare to an American? Sticky.
Now when you start putting these diverse elements together you end up getting what may be termed 'a western rating'. Here are some examples:
- Japan fulfills c) and d) for sure but falls short on the other factors.
- Korea ticks c) and d) but contains many Christians, so with a nod to a). Still not enough boxes ticked though. Next!
- Germany on the other hand ticks the boxes for a), c), d) and e) but isn't an entirely English speaking nation, so does it count itself as western as say the last candidates? This example shows you how tricky category b) is.
- The USA ticks all the boxes but then so does the UK. So are they each of the same Western rating?