One 300kt bomb targeted on the middle of Chicago doesn't even reach outside of city limits, except maybe on the west side. In order to also get the Fungal Vale, they'd have to airburst the Tsar Bomba, a 50 megaton fusion bomb, over that point.
More realistic: a bunch of smaller bombs hitting strategic targets like the airports, the Loop, major rail yards and intermodal terminals, things like that. That might mean the Fungal Vale got edge effects from one of those blasts; if bad guys targeted the Ford plant with something that would probably insure it--but there really isn't much in the way of strategic targets out here.
But the heat pulse from an airburst of a 300kt weapon only goes about five miles--of course, this "simulator" gives us no indication how how high that airburst is, so we have to take that with a grain of salt, but I'd assume that because the mission of the "simulator" is to scare people, they'd want to maximize the simulated carnage, and so would pick a reasonable optimum airburst altitude.
So here's the thing: to completely eradicate the Chicago area's strategic value, you'd have to pepper it with perhaps a dozen 300kt bombs, or at least a score of 150kt bombs--and there is only one country on the planet, other than the US, that has an arsenal that size.
Other nuclear scaremongers say that China has perhaps 300 weapons. With an arsenal that size, I'm not sure Chicago merits more than a handful of bombs, and those would be targeted on major transportation nexi.
Like a lot of people, I overestimate the destructive capacity of nuclear weapons. And I know enough about them to know better! But this web site shows me just how much I overestimated; one 300kt bomb going off atop the
And a 300 kt bomb is a big piece of hardware to lug up 100 stories. I'm a lot less worried about terrorists with nukes than I was before seeing this thing; and I'm not worried about a major foreign power attacking us with nukes because--as the history of the Cold War shows--no one is that stupid.
North Korea could manage one or two nukes at best, and they'd be perhaps 150 kt, and they wouldn't be targeted at the midwest in any event. There are much more important strategic targets elsewhere in the country.
That's a relief.