On this day, 54 years ago, June 21, 1971 (May 29, 1971, the lunar calendar), thousands of Japanese students demonstrated to demand the return of Okinawa Island. Students use bamboo flagpoles to break police lines On June 21, 1971, riots broke out as Tokyo students protested against a US-Japan agreement to return Okinawa. During World War II, Allied forces and Japanese forces fought fiercely on these islands, and after the end of the hostilities, the islands were managed by the United States. On June 17, the United States and Japan signed the "Return" Agreement of Okinawa in Washington and Tokyo respectively, which came into effect on May 15, 1972. Under the terms of the revised agreement, the United States reserves its right to base a military base on Okinawa. This made the Japanese feel cheated, and as a result, thousands of left-wing students staged protests in Tokyo, demanding the unconditional return of the island to Japan. Serious clashes broke out between them and police, and 89 people were arrested.