I'm attempting to flesh out the history to a sci-fi novel I'm currently writing, which is set in the future.
- Several hundred years prior to the beginning of the story, lack of resources lead to several protracted world wars that eventually culminate in a nuclear holocaust and, potentially, chemical/biological warfare.
- The majority of the planet’s population is killed in the wars and the subsequent fallout/environmental crises that ensue.
- A pocket of humanity remains in an isolated area of land, separated from the rest by sea on most sides, and a border made up of radioactive wasteland caused by the destruction and meltdowns of a chain of advanced nuclear power stations, which they cannot cross.
- They have become equally, if not more, advanced than they had been pre-war, and have begun space exploration.
The rest of the planet is somehow also still uninhabitable several hundred years post-nuclear holocaust, however I need a good enough reason for why this might be the case.
I can't figure out a reason (scientifically accurate) good enough for why this particular pocket of humanity wouldn't have just gone around the radiation via sea/air and inhabited the rest of the planet by the start of the novel. However, I desperately need them not to be able to, for several hundred years at least.
A large-scale "radiation wasteland" at this point, several hundred years post-war, isn't realistic - if humans were die, then so would the flaura and fauna and, I assume, the whole eco-system would collapse and therefore humanity would go extinct. Also, from my research, it seems that the Ozone layer would take too much damage (in a situation where that could happen) and that would also kill everyone/thing off.
My question is this - is there any potential subsequent result or side effect of a large-scale war that could cause large areas of the planet to become uninhabitable for humans, but keep the eco-systems and ozone layer intact enough for humans to still thrive without untoward difficulty in some other area of that same planet?
Will I have to bring out the bio/chem weapons in to play?
Thanks in advance!