You know, GE, that's a fair question (but I would definitely not call it a simple question).
Trying to simplify, I frankly believe it's all relative.
That is, relative to what you know, what you are used to, how you are equipped, and especially who you know, etc.
My primary consideration for determining effective preparedness is the people themselves. In other words, are your strengths anchored in a family or community? Note that the family/community can be defined in a number of different ways.
Bottom line, lone wolves really don't last long in crisis (except in Hollywood blockbusters). Well-intentioned groups add up quickly well beyond the sum of their individual parts.
Environmentally--we have to presume most of us are best adapted and suited to survive in the region in which we live. I for one would do poorly in a jungle environment or other torrid zone. I would hate to also have to endure arctic conditions for long, but I would be better off there than on the equator because of what I know and what I have experienced.
If you press me, I am inclined to recommend the US Midwest. Certainly there are pluses and minuses for any locale if you are looking for reasons to move or to stay somewhere. But to look for greener pastures ... well, you know you can always spot seemingly higher ground than where you sit today.
Ideally--anyplace where there are reasonable growing seasons, natural wildlife habitats, traditional community lifestyles, and moderate climate would pretty much make it in my mind as a place to be satisfied and optimistic about chances for the future, whatever cards life deals.