Circumcision is not widely practiced in Japan, with only a small percentage of men opting for the procedure. It was introduced as a medical practice by Western doctors during the Meiji period but became less popular after World War II due to its association with the American occupation. Circumcision in Japan is primarily performed for medical reasons such as phimosis or recurrent balanitis, and religious circumcision is not prevalent since none of Japan's religions require it. The decision to circumcise or not is a personal choice that varies from person to person, and there are alternative procedures available for treating conditions such as phimosis. Given that circumcision is not widespread or part of Japanese culture, it is unlikely that it will become more popular in the future unless there are significant changes to attitudes towards the practice.