Earlier quoted context omitted.
> the military and public would not want to die in a nuclear inferno to defend national sovereignty Erm, it's kind of demanded for people to go out and die to defend national sovereignty in nations that have a draft. For myself, I'd prefer to be vaporized than bleed out in a trench if it really comes down to it.
Realistically speaking you'll die of an infected and untreated burn wound though, the severe blast and burn area is just much much bigger than the fancy "everything just goes poof" core.
The problem is that if you eliminate ~20% of a nation's population, supply chains, continuity of government, and the economy aren't going to last long. Social organization breaks down much more widely than people die. The resultant pullback of all the trapping of society - reliable food supply, clean water, transportation infrastructure, electricity, heat - is going to kill many more people than the nukes will.