Nuclear war is like cancer.
It's very bad, but none of the recipes for prevention inspire confidence. Maybe there are a few actions that will reduce the risk, but mostly one just hopes. At least with cancer there are statistics, but one can't even know the odds of getting into nuclear war or of surviving it. Freeman Dyson is a well known theoretical physicist. In the forties, he helped found quantum electrodynamics, a theory whose numerical answers agree with experiment to eleven decimals.