The possibility that world annihilation rests with the twitching fingertips of a dictator in North Korea and a narcissist in Washington motivated me to focus the second science history podcast on nuclear disarmament.  As a bonus, we also discuss renewable energy, another fitting topic at a time when the United States stands alone as the only country in the world that is withdrawing from the Paris Agreement on Climate Change.  My first guest is Jose Goldemberg, a physicist who has played a central role in the development of Brazilian science and policy for half a century.  Jose’s comments are put into the historical perspective of Cold War events by my second guest, Frank N. von Hippel, a professor and co-director of the Program on Science and Global Security at Princeton University and the Woodrow Wilson School of Public and International Affairs.