There are a number of reasons why Christianity has not yet been successful in Japan, i.e. the interaction between worldviews, theologies, missiologies and society as well as historical-political factors have prevented this. Understanding these factors may help the reader in answering the question above.

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four major errors committed by Western missionaries in Japan throughout history: (1) Eurocentric approach, (2) lack of consideration for cultural context, (3) competitiveness and (4) direct or indirect involvement with western political agendas.

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The word the Japanese use for “sin” is tsumi **which is the same word used for “crime”, so when an evangelist or a missionary claims, “we all have sinned” or “we are all sinners” the average Japanese may not understand what is being—he or she does not consider himself a "criminal**".

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Japanese are in certain way disappointed and confused when it comes to the nuclear attacks on Hiroshima and Nagasaki. Historically, Nagasaki is a well-known center of Japanese Christianity.It was not only the location of the largest Christian Cathedral in the Asia (St. Mary’s) but also had the largest concentration of baptized Christians in all of Japan. These facts make it even more difficult for the Japanese to understand why a Christian nation such as America would to drop a nuclear bomb on a Christian cityimmediately after Japan’s surrender when thousands of American missionaries were sent to Japan to Christianize the nation.

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The corporatism/individualism dichotomy can also be found in the concepts honne and tatemae. Honne refers to ‘informal, personal reality in disregard of social parameters’, while tatemae means ‘official, public and socially required or politically correct.’ Honne is an opinion or an action motivated by a person’s true inner feelings, whereas tatemae is an opinion or action influenced by social norms. Thus, honne refers to a person’s deep beliefs or intentions, while tatemae refers to motives or intentions that are the result of social attunement, those that are shaped, encouraged, or suppressed by the norms accepted by the majority. These two concepts are often considered dichotomous and in conflict with the genuinely held personal feelings and convictions of those who are socially controlled. It can happen that a person in his/her honne chooses Jesus Christ silently and continues with this usual lifestyle without disturbing the group harmony. He or she does this by suppressing the honne in such a way that his/her decision will not be openly noticed by the groups to which the person belongs. In short, Christianity in Japan cannot succeed if it disturbs the spirit of corporatism and undermines the individual’s sense of belonging to these groups.

http://www.projectjapan.org/pj/Article/Entries/2013/8/16_Why_Is_Christianity_Not_Widely_Believed_in_Japan.html