It’s 61 years since Hiroshima was nuked and 45 years since Herman Kahn’s definitive work. We survived the Cold War without a nuclear exchange because both sides followed Kahn’s analysis. But such wars are quite likely in the next decade.
Kahn used games theory to examine the behavior of competing nuclear armed rational players. He concluded that both sides possessing visible and credible second-strike capabilities minimized the probability of a nuclear exchange. He also reassured us that the US would survive a nuclear war.
In spite of the bitter rivalries of the Cold War, there was no nuclear exchange.
But now we have primitive, non-rational players – North Korea and Iran – supported by a semi-rational player – China. So none of the deterrence rules apply.
The Mullahs think they’re going to heaven with their ration of virgins, so they’re hard to deter. A paranoid psychotic leads North Korea, so he can’t understand consequences. China is arming both, and may invade Taiwan, in spite of its absolute dependence on exports to the US.
So, for the purposes of life planning, I’m assuming that in the next 5 years we’ll see:
One or more 1,000 Megaton nuclear exchanges between some mix of North Korea, China, Japan and Taiwan.
A 500 Megaton nuclear exchange in the Middle East.