[mikeash]

I'm not sure what your first link says, but the other two generally seem to agree with me. The second one gets EMP wrong, as everyone does, but Wikipedia covers it well enough:

http://en.wikipedia.org/wiki/Nuclear_electromagnetic_pulse

I'm rather confused as to why you think that map suggests that I'm grossly underestimating the effects. It lines up perfectly. For example, select a Topol and put it over downtown Manhattan. You see that the fireball covers a few blocks, the death-by-radiation zone covers most of downtown, as does the destroy-all-buildings zone, the destroy-residential-buildings zone reaches up to Central Park, parts of Brooklyn, and into New Jersey, and severe burns for exposed people and random fires started by the flash goes out to most of Manhattan, much of Brooklyn, and big chunks of New Jersey. The zone in which "duck and cover" would save lives (outside the death-by-radiation area, inside the death-by-collapsing-residential-buildings-and-flying-glass area) covers almost 100km^2 and probably a couple of million people.