japan is not the only buddhist country, it is not a fully buddhist country, and the forms of buddhism practiced in japan are not the same as other types of buddhism. the problems of japanese depression and suicide are more related to their culture of honor and familial/clan expectations, the competitions of their economy and their failure in the second War, which is more from shintoism than buddhism. buddhism in fact has been seen as a contradictory force to traditional japanese warrior ethos for most of japanese history, and the forms of buddhism that exist in japan were molded to fit their culture, like shingon and nichiren