What is the risk of nuclear war?
Are you asking what the probability is? Right now, it's slim, but as more idiots get nukes, like Iran, the probability rises!! If you're asking what is the risk to humanity is, it's extremely high!
The End Of The World "Apocalypse".
The risk of it? Unfortunately possible at all.
The risk of everyone dying a slow painful death :(
Death to everyone exposed to radiation and then becoming zombies
Currently? 0. If however the world were to suffer a complete social and economic collapse? 99%. People facing starvation and/or thirst will do amazingly horrific things to satisfy such needs.
Total human annihilation!!
I would watch Korea and china very closely. These two governments are unstable in my opinion