Vowell is somewhat obsessed with presidential assassinations and she focuses here on Lincoln, Garfield and McKinley and their assassins. She literally goes on assassination vacations. She goes on daytrips, finds plaques all over America and through some very interesting observations and droll commentary, I learned more about American history and some old guy presidents than I ever knew. And she did a great job of writing a history book full of facts and connections - for example, Richard Todd Lincoln was present at, or near, all three of those assassinations- without losing my interest. She doesn't explain things linearly and it makes for a very chatty, enjoyable read. I imagine if you were American and knew even a little about these characters, you would enjoy the book even more.
Vowell makes some interesting connections to current events and presidents, since the more things change, the more they stay the same. History repeats itself. There was mention of the Chicago World Fair, the subject of another book Devil in the White City by Erik Larsen which is making me want to read that as a book for this challenge. I borrowed the book from a student and the fact that the Chaicago World Fair was mentioned so often in this books means it is fate (McKinley was shot at the world fair in Buffalo) that I read it.