The Nobel prize-winning physicist Hans Bethe, was a key figure in the development of the nuclear energy and weaponry, including the ones dropped on Hiroshima and Nagasaki. Yet, he campaigned for nuclear power and nuclear disarmament. The Guardian notes in his obituary,

Yet, in nuclear affairs, Bethe was perhaps the most polished, vocal and convincing of establishment figures. He balanced vigorous participation in disarmament negotiations against cautious but unwavering commitment to nuclear energy, which he saw as the only available bridge to safer energy technologies in the future.

He argued persuasively that the 1986 Chernobyl disaster was a product of design, engineering and control failures that could not occur in the west. And, like many establishment physicists involved with nuclear affairs, he sought to explain to an increasingly sceptical public, the virtue and value of applying risk assessment techniques to show how safe the nuclear option would be in the future.