Well, you have to also admit that there wasn't a concerted effort to convert the Chinese populace en masse. You know what I mean? For example in the Philippines, the majority of the people were actually Muslim prior to the Spanish arrival ( in fact before Spain's arrival in the Philippines, it would be even hard to differentiate the society in the Philippines from say that in Java Indonesia, Sumatra, Borneo or even Peninsular Malaysia. Understand? But the Philippines underwent a forced conversion program that was instilled by the Spanish Audencia (Religious Arm of the Spanish Government). So you see how after nearly 400 years of Spanish rule, the majority of Filipinos are now Roman Catholic , the religion of Spain.
The same way applies in say Korea (South Korea). Before the Korean civil war , Korea as a society was actually strongly mahayana buddhist, and also there was a significant portion of Korean population that also practiced Shintoism , since Korea was for almost a century influenced by Japanese culture , you know what i mean? After Korea was granted indepedence and after the Korean civil war, the high amount of American presence also led to American missionary activities in the country --- specially presbyterians, methodists, catholics, and even mormons (latter day saints). So you see that is the reason why today Korean population is now 33% Christian. There was a converted effort as you see.
China, on the other hand is a totally different country. China is not a small country like say Korea, or Philippines, you know that. China is a civilization starter, She is the progenitor of Confucian society, the progenitor of what is now Japan and Korea. So there is a strong cultural influence in China to retain the family name, to retain the practice of ancestral worship through filial piety. Chinese culture places importance on the family name -- and the role of the son in this dynamic. Very much the same was as Japanese. You see? Japan has been defeated by the United States, in fact, there are even over 40,000 American troops that operate around Japan --- yet Japan does not have a significant Christian population, Muslim population, despite being exposed to these religions. I'm not saying that there are no Christians in Japan, just that there are not that many as compared to say in South Korea or even in China, you know what i mean? The reason for this is because Japanese culture is very strong -- and so is the Japanese identity. Similar in dynamic as the Chinese one. This has been the reason why Japan and China has been, for a long time, resistant to foreign religions either than Buddhism.
