What ever happened to acid rain? I think if the acid rains killed off much of humanity, they should melt all the zombies and wildlife, trees, houses and everything that can dissolved by acid, as well.
For being a xenophobic, highly reactionary, well-armed populace in this society, I wonder how there are zombies at all, seeing as a basic survivor with a basic rifle and basic weapons or a compact sedan can safely eliminate any number of zombies, fungus, ect and clear a whole town alone, let alone a whole police department, national guard unit, robot armies, ect.
I noticed the lore now says 'high explosives' instead of 'nuclear warheads' in regard to the attempt to stop the cataclysm. I think the latter makes more sense to explain all the drained batteries in cars and broken generators and computer terminals, only hardened or well insulated electronics survive. If they have nukes and they need violence to keep the world intact, they'd use them for sure.
How does the whole blob-infection thing work again? If it's in the drinking water, it's safe to assume every survivor and creature everywhere is infected and will reanimate on death. If it can survive the processes used to service the tap water supply, it can survive in any source of water, so everything in New England has done caught da blob.... Which makes me wonder, if a blob-infected woman gets pregnant, does the kid get the blob, too? Gets born and dies with this alien thing in it forever, doesn't that destroy any chance humanity has to win? How about a miscarriage? The fetus goes zombie-mode?
Also I was always under the impression the rest of the world outside of New England is relatively intact, if not thrown in absolute chaos and economic collapse... I pictured New England as some sort of Stalker-style dead-zone and the rest of the world is experiencing total war and anarchy and losing, but not the whole-sale infection and death, so the whole military is off-map fighting with moving zombie hordes and portals and holding the line and considers this area the game takes place in basically a lost cause, with just some token stay-behinds. Either way, too busy to help, but still there, just because it doesn't make sense everyone in the world would die in 5 days when human technology is so powerful....
So this conflict with China and Russia and the US is such a point, maybe it means the world had a nuclear war at the same time as the cataclysm? The US nukes it's own country to deal with the portals, provokes a nuclear attack by China thinking the launches are aimed at them, and it goes back and forth in the chaos. End result is a barely-functioning government, mostly dead people around and EMP-related damage to electronic systems. Other countries not nuked have EMP damage, imploded economies and are dealing with dimensional weakening anyways.
Probably otherthinking the game, but hey, I like to be immersed in fiction.