Atomic bomb survivor Tsuboi Sunao was one of the leading voices calling for the abolition of nuclear weapons. He died in October at the age of 96. On the day of the bombing of Hiroshima, he was just 1.2 kilometers from the epicenter and barely survived. He dedicated the rest of his life to the fight against nuclear weapons. And in 2016, he met then US President Barack Obama, the leader of the country that dropped the bomb on his hometown. We look back on his life and hear from people who knew him about the message he wanted to convey to future generations.