What Is Everyone So Worried About?
A one-megaton blast would create a firestorm covering a hundred square miles... but the U.S. is about 3.8 million square miles, so by far, most of the country wouldn't be caught in a deadly firestorm. And let's say our first worst-case scenario has already happened, and we're all now forest-dwelling savages. Then our nation could get hit with a nuclear bomb, and most of the country wouldn't even notice. We'd just go along trying to kill deer with pointy sticks, as usual. So instead of these worst-case scenarios stacking, they kind of cancel each other out.
So there's a lot out there that people worry about, but it's not that bad when you really think about it. I'm optimistic for future generations. I mean, I'm not optimistic for our kids, as they'll directly inherit our mess. Nor for our grandkids, who will get it even worse. And if the country is still around long enough, I'm just glad I'm not our great-grandkids -- oh boy, are they going to have crazy lives. But I am optimistic for generations far in the future. Maybe ones not even of the same species -- perhaps bird people who arise after the collapse of mankind. For they'll dig up the remains of our civilization and piece together what happened from fossilized iPods and long-buried "Hope and Change" campaign buttons and hopefully learn a lot from our mistakes so they don’t repeat them. See, this all works out in the long run. But not the long, long run, as eventually the sun will explode and swallow the earth.
The point is, let's not worry so much. Eventually everything works itself out. So keep your chin up, practice your basic survival skills, and if you have any good wisdom, get it to those who'll need it by putting it on something that can survive being buried for thousands of years.