Sunao Tsuboi

On October 24, 2021, Tsuboi died of arrhythmia due to anemia in Hiroshima at the age of 96. He was survived by a son and two daughters.

He had criticised Japanese Prime Minister Shinzō Abe for attacking Japan's postwar commitment to pacifism. In 2015 he and other atomic bomb survivors asked Abe to drop the unpopular security bills then being passed by Abe's administration.

After retirement from teaching, Sunao Tsuboi became more involved in anti-nuclear and anti-war activism, participating in sit-ins, demonstrations and rallies. He travelled across Japan and abroad in his many campaigns and repeatedly stated that he wanted nuclear weapons to be abolished. He became the co-chair of Nihon Hidankyo, a Japan-wide organisation of atomic and hydrogen bomb sufferers, in 2000. In 2011, he was awarded the Kiyoshi Tanimoto peace prize for his efforts in activism. He made many speeches to students on school excursions to Hiroshima, foreign visitors, and many others over the years, and met with Barack Obama, the first sitting US president to visit Hiroshima, in May 2016. In recognition for his work campaigning for the abolition of nuclear weapons and support for other hibakusha, he was named an honorary resident of Hiroshima in 2018.

Tsuboi became a teacher as the hours were not so demanding and teachers received a lot of days off. He taught mathematics at a women's college and at other schools including Ondo-Cho Junior High School. Close to August 6 he would tell his story to his students. He was known as "Pika-don Sensei" or "Mr Flash-Bang", referring to the atomic bombing. He became the principal of a Junior High School, and retired in 1986 after serving as the principal of the Kamezaki and Jonan Junior High Schools.

In 1945, he was a student of the Hiroshima City Technical School (present-day, the Hiroshima University School of Engineering). On the morning of August 6, he had just eaten breakfast at a dining hall named "Shima no Kaori" and was invited to have a second breakfast with other students. He declined as he was concerned that the young woman behind the counter would consider him a glutton. When the bomb exploded soon afterwards, he was walking to school and he became badly burned. Everyone in the dining hall was killed.

Sunao Tsuboi (坪井 直, Tsuboi Sunao, May 5, 1925 – October 24, 2021) was a Japanese anti-nuclear, anti-war activist, and teacher. He was a hibakusha, a survivor of the atomic bombing of Hiroshima, and was the co-chair of Nihon Hidankyo, a Japan-wide organisation of atomic and hydrogen bomb sufferers. He was awarded the Kiyoshi Tanimoto peace prize in 2011.