Take it from a sailor, we are no where near a war. Why? Global Economies. I can, and have, go into a multiple hour long discussion about this, but I don't have time right now. Plus every single nuke in the world is in an extremely rusted out state it will take a miracle to get them flying. America's nukes launches on Floppy Disks (Look those up youngsters, they're decades old.)
Basically though if any major nation tries to declare war on another major nation, their economies would crash and burn within HOURS and revolution will be in a matter of days. America almost had a civil war over our involvement in Vietnam, due to the draft and the taxes needed to pursue it. No politician in their right minds would go to war with another major power. It would be political suicide.
It will never happen. The world will end due to the environment, not because of a nuclear holocaust.