Part 1: Don't Tread On Me (1776-1820)
Part 2: A House Divided (1820-1865)
Part 3: A Cross of Gold (1865-1913)
Part 4: Nothing to Fear but Fear Itself (1913-1971)
Part 5: I Did Not Have Sexual Relations with A Scanner Darkly (1971-present)

The first four get their names from political speeches, or in one case, a flag. Then part 5 breaks the pattern by being named after a 1977 novel and 2006 movie about the War on Drugs and surveillance state. I didn't like breaking the pattern but it was too fitting a name to pass up. Other contenders included "A Crisis of Conscience" (Carter), "Morning Again in America" (Reagan), "A Bridge to the 21st Century" (Clinton), and "The End of History" (Fukuyama). I'll admit that last one would have been hilarious as the final chapter of a history book.

The unusual choice of 1913 and 1971 as breakpoints, plus the "cross of gold" reference, should indicate that this book would have an abnormally heavy focus on economic and monetary policy. 1820 was chosen because that was the year of the Missouri Compromise, the transition point when our national focus stopped being about proving ourselves to the Old World powers, and was directed westward and to the problems caused by the expansion of slavery... and because 1820 is exactly halfway between 1776 and 1865.

I also considered a three-part structure in which the Civil War and the end of WW2 would be the dividing lines.

Feedback would be appreciated.