"...to cover every square km. We dont have that many..." One does not have to rake every piece of soil in order to wipe out the entire life. The oceans would g

"...to cover every square km. We dont have that many..." One does not have to rake every piece of soil in order to wipe out the entire life. The oceans would get the radioactive lavement of the soil and cycle that back on the land over and over though radioactive rains. This affects especially the bottom layer of the food chain, which cause chain's partial (if not total) collapse. In the end there is the possible nuclear winter that may render almost the entire planet inhabitable for all life forms. (Spores, bacteria, algae or other microscopic life forms may resist in hibernation to thrive again someday, but that is not called "living" through the event.) The reality is that there wasn't in our planet history any extinction event that involved nuclear contamination of every available living habitat (among other hostile-to-life effects), and speculating about it and about if it would or not be destructive enough, feels to me a little bit like playing with madness here.