Sarah Vowell is a New York Times bestselling author of seven nonfiction books on American history and culture. By examining the connections between the American past and present, she offers personal, often humorous accounts of American history as well as current events and politics. Her book, “Lafayette in the Somewhat United States,” explores both the ideas and the battles of the American Revolution, especially the patriot founders’ alliance with France as personified by the teenage volunteer in George Washington’s army, the Marquis de Lafayette.