A national flag and anthem are supposedly symbols of national unity. So it is with Japan's Hinomaru flag and "Kimigayo" anthem. Yet they remain a subject of simmering controversy, particularly in the realm of public education, because of the nation's history of militarism during and before World War II. Last month, more than 170 senior high school teachers in Tokyo were reprimanded by its board of education for refusing to sing the anthem at graduation ceremonies.

Those teachers, the board said, disobeyed its October 2003 directive spelling out proper ways to conduct graduation exercises, from how to display the flag to how to deliver diplomas. The directive, which was issued to all public high schools in the capital, says, for example, that the flag should be placed prominently at the front of a platform and that all teachers present should sing the anthem, standing from their designated seats while facing the flag.

The education board sent monitors to schools to make sure that the ceremonies are conducted according to protocol. Reportedly they kept a close watch on individual teachers, based on their seating arrangements, to find out who did not stand up and sing. It was an unusual inspection that seemed to symbolize education authorities' over-enthusiastic efforts to ensure compliance.