Rikkitic:What I wonder, and what the article doesn't mention, is what might happen to us when the military remnants of destroyed countries realise this is a good place to be and start heading this way. With the northern hemisphere a radioactive wasteland and no remaining international order, what is to stop any surviving warships from simply moving in and taking over? Could we even resist a modern aircraft carrier or battleship?
There have been numerous speculative-fiction books that cover something like this, variants being groups with modern weapons getting teleported into the past. In pretty much every case it moves within about one chapter from "we have better weapons than anyone else here" to "we're running out of fuel/ammunition/food/supplies and there are two million of them and a thousand of us and we've rather upset them, what's our exit strategy?".
In this particular case it'd also be "... and about half of us are dying of radiation sickness and the rest of us have been eating contaminated food for the entire trip here". So I'm really not worried about this scenario.