Western Civilization did quite fine without Christianity
WOW. That statement you make demonstrates how little you know about Western Civilization
It can be argued that the spread of Christianity from southern to northern Europe expanded the idea and ideals of the west to the formerly barbarian lands. Moreover, it is true that the conversion of Charlamagne led to the creation of a Holy Roman Empire that was Germanic, yet now open to the ideals of the south, channeled via a now-common Christian heritage.
Nevertheless, the "West" (inclusive of the Americas, there is no "Latin American Civilization"), as an idea and a set of ideals preceded the above by thousands of years, and will survive the decline of Christianity (all but complete in Europe, there is not ONE European state that is seeing a Christian revival). The question is, will it survive the "rise of the rest," particularly if "the rest" have imperial ambitions.