Obtain, or envision if you can, a map of the world. Locate Prague. Extend a line towards and through the geographic poles such that the map is divided into two hemispheres. Take a crayon. In the Atlantic Ocean trace a large capital W. In Asia Minor trace a large capital E.
Ponder on this for a time. Reflect the extraordinary ties of culture, technology and geography that tie the W side together, and the contrasting ties that bind the E side together. Now hold the map in your open palm and rapidly compress your hand into a fist, because the map is absolute bollocks and the chaotic crumpled folds give a far better impression of what the world is like. You should know - you were just contemplating the cultural similarities of Ireland and the Democratic Republic of Congo, or Mongolia and New Zealand.
The North-South divide sometimes mooted is fairly useless as well. It would have the people of South Africa petitioning for asylum in Moldova.
The West is shorthand for Western European Civilisation. It stems as a concept from the split of the Roman Empire into Western and Eastern empires about two millenia ago; it was vaguely reinforced by the Cold War. It is characterised by traditions of Christian religon and belief in the worth of the individual. It is a byword for technological and mercantile success. And it no longer exists.
Much of Western Europe is Christian in name only; most are vague agnostics. The Phillipines and Brazil are far more devout, and are not usually considered part of the West. Mercantile and technological success has never been exclusively Western European - printing, gunpowder and the magnet all came from China through Arabia and Central Asia. Even using The West as a tag for twenty-first century wealth ignores the second largest economy in the world in Japan. The tradition of civil liberties formalised by democracy are firmly planted outside Western Europe - for some of last century more firmly than within it.
The traditional Western countries seem to be run by white men. Is The West a racial distinction? Only if "whites" are a race, Italians, Spaniards and Russians are not, and people such as Colin Powell are ignored.
Is The West a description of political power? The UN Security Council suggests it is not a good one.
So what is Western culture if it has no distinguishing attributes of geography, economics, religon, technology, race or politics? It seems to me that as it is usually used, Western means "like America". America wasn't even part of the Roman Empire. Using Western this way has unfortunate implications. It implies that the USA is the only model for a successful industrial democracy. And it implies success as a nation is predetermined with geographical solidity. It assumes, say, Pakistan, could never be a rich, industrial democracy, because they aren't part of The West.
Words have an intimate relationship with our minds that makes people loath to change what they say. This is more a call for precision than political correctness, though. In its cultural context, West is a useless and coagulated term. I offer, in conclusion, some synonyms. American, liberal, industrial, democratic, corporate, European, rich, English, Teutonic, secular, arrogant, free.