Additionally, the idea that we could kill everyone on earth or kill everyone x times over is based on the idea that we are rounding up people and putting them i

Additionally, the idea that we could kill everyone on earth or kill everyone x times over is based on the idea that we are rounding up people and putting them in perfect concentric circles based on optimum detonation height and having everyone in the kill circle. I mean, yeah, we could do that with the gun ammunition and kill everyone too, but it's ultimately a meaningless number. Nukes are very very expensive to build and maintain. They are very destructive. But there is a lot of emotional arguments tied up in this that makes rational discussion about what actually happens almost impossible. Radiation is either hot and thus has a very short half life or is long and also not particularly dangerous. The only element that straddles this line is cobalt. Hot enough to be dangerous, long lived enough to seriously impede life returning. To date it isn't known if anyone really has cobalt bombs, Russia might if anyone does. But that's the closest thing I've ever seen that's a potential long term mass area denial weapon.