I agree with Richard, although increasing odds on Iran/NK. For those who haven't read.
Patriots: Surviving the Coming Collapse James Wesley Rawles
Part novel, part survivalist-handbook,
Patriots tells of a small group of friends facing every American's worst nightmare - the total collapse of society. The stock market plummets and hyperinflation cripples commerce and then a seemingly isolated financial crisis passes the tipping point when an unprepared government fails to act. Practically overnight, the fragile institutions of democracy fall apart and every American is forced to survive on their own.
Evading mobs of desperate, out-of-control citizens who have turned Chicago into a wasteland of looting and mayhem, this novel's protagonists make their way to a shared secure ranch in the wilds of northern Idaho. Here the survival-driven group fends off vicious attacks from the outside and eventually assists in restoring order to the country. The compelling, fast-paced action-adventure novel has readers jotting notes and referencing the book's impressive index for informative survivalist tips on everything from setting up a secure shelter to treating traumatic flesh wounds.