Did you watch the movie? I'm simply quoting the analysis. They modeled their results by taking the actual plume from a test blast of similar size and overlaying

Did you watch the movie? I'm simply quoting the analysis. They modeled their results by taking the actual plume from a test blast of similar size and overlaying it on the U.S. mainland. So they are working from recorded data, not a model. Wellerstein does not model a lot of the effects in Nukemap, as he admits. The fallout issue depends on the height of the blast, the material attacked, etc. A ground blast lofts huge amounts of radioactive material into the upper atmosphere. Depending on the firestorm to follow there is yet another source of uplift. Low background steel (https://en.wikipedia.org/wiki/Low-background_steel https://en.wikipedia.org/wiki/Low-background_steel) is highly valued because it is not contaminated by nuclear tests which affect all post-war, pre-1963 manufacture. Chernoble affected Europe in detectable amounts and it wasn't even a warhead. Just yesterday I read an article (http://investmentwatchblog.com/a-nuclear-spent-fuel-fire-at-peach-bottom-in-pennsylvania-could-force-18-million-people-to-evacuate/ http://investmentwatchblog.com/a-nuclear-spent-fuel-fire-at-...) pointing out that a fire in the spent fuel storage in Pennsylvania would affect millions (http://scienceandglobalsecurity.org/archive/sgs24vonhippel.pdf http://scienceandglobalsecurity.org/archive/sgs24vonhippel.p...). And that's just a fire, not a Nuke. If the Nuke hit a spent fuel pool things would get ugly fast. I admit it might not kill everyone. But it would certainly ruin their morning coffee.