Is the doctrine of nuclear deterrence still relevant?

​In a rare joint statement issued on Monday, five of the world’s most powerful nations pledged to avoid nuclear war. In this episode of ‘The Foreign Desk’, we examine the doctrine of nuclear deterrence. Does possessing a nuclear deterrent make the world safer? Is a world without atomic weapons even possible? And what’s it like to be the person tasked, if the order to unleash the apocalypse ever did come, with turning the key? Andrew Mueller speaks to Tom Nichols, Margaret MacMillan and Dana Struckman.