I really hate some things here. They have been discussed for years.
The nuke, according to Mike was in 5KT range. It was detonated in the centre of a war torn, besieged city, the centre that was and actual warzone. There were not many people there. Even if there were, there wouldn't be even close to half a milion.
Picture this. A 20KT nuke, droppet over a centre of an unsuspecting city, far from any fighting, in the rush hours caused between 90 thousand to 140 thousand fatalities. The Arasaka nuke would cause 5-10k casualties, tops. And again. The nuke doesn't even destroy the entire tower (it is clearly stated in jupstart) If it's the case, the nuke is minimal yeld device (not achievable practically at this moment, but CP is sci-fi) ranging far below 0,1KT. The verdict is, less than 1 thousand die in the nuking of NC, probably not a single person outside Arasaka Tower. Also, after the detonation, Morgan and Adam were trading blows on the collapsing roof...
"It killed half a million people, save those in the ground zero..."
As for the Times of Red... ONE nuke, a few orbital drops, 3 years of VERY LIMITED fighting. Why limited? There're two corps fighting. They can hardly field 200k troops all over the world at all time. Sure, they used some proxies in the form of smaller corps and 3rd world armies, but still. It is even clearly stated that by the time of nationalizing Militech, the war caused 50k casualties all over the globe. A lot. But more pople die yearly in gun related incidents in the US alone, and it does not cause the end of the world
Second World War in which THREE nukes were used, each five times more powerful than Mike's nuke, every major citry between Moscow and Brussels was turned into rubbles, some of them burned to the ground, I only mention Europe. And guess what... no times of red...
I know I'm picky, but even writing an RPG game lore one could use some common sense. And at least read what he's written 22 years ago