Comment by dontbeevil1992

I might not have said this clearly enough - I'm not saying that conditioning on "did we have a nuclear war" will change the probability to be less. I'm saying that the event "did we have a nuclear war in year n" is not independent from "did we have a nuclear war in year n+1" "n+2", ... because there are shared factors influencing them. Therefore the model of independent probabilities multiplying year over year and seeming to imply that nuclear war is inevitable because (1-p)^n goes to 0 as n grows doesn't make sense mathematically speaking.