Pope Francis, possibly the single most influential person on the planet, condemned not only the use but also the ‘very possession’ of nuclear weapons on 10 November.
Previous leaders of the 1.2bn-strong Roman Catholic church had justified keeping nuclear arsenals (to deter other countries from using them).
The pope gathered hibakusha (survivors of the 1945 atomic bombings of Hiroshima and Nagasaki in Japan), 11 Nobel Peace Prize-winners, UN officials, priests and diplomats for a two-day disarmament symposium at the Vatican.