The Bulletin of Atomic Scientists’ has moved its Doomsday Clock to 100 seconds to midnight (a metaphor for catastrophe), as close as it has been since the Clock was created in 1947. According to the Bulletin, the 2020 reset responds to the augmented existential risks of nuclear war and climate change, compounded by the risk of cyber warfare. The links between these threats, particularly the nuclear threat and the climate threat, abound. Nuclear-armed countries like China, India, and Pakistan all have populations that outstrip their access to freshwater resources, a problem that climate change will exacerbate. The resulting social stress will strain social and political institutions, and make conflict ever more likely. The way to set the Doomsday Clock back is for the US and Russia to restart diplomacy around nuclear disarmament and cyber warfare, the US and other signatories to recommit to the Iran nuclear deal, and all countries to bolster their commitments to Paris climate agreement. Instead, key global leaders turn the other way as the clock keeps ticking.