American historians are better at history than math. So argues Kevin Phillips in his new book on the origins of America’s war for independence.

In 1775: A Good Year for Revolution, Phillips says that for too long historians have listed 1776 as the pivotal year in the beginning of the American Revolution. The correct date, he says, is 1775. As he writes in the book’s opening pages, “If 1775 hadn’t been a year of successful national building, 1776 might have been a year of lost opportunity, quiet disappointments, and continued colonial status.”

Yes, the Declaration of Independence and the formal separation from the British occurred in 1776. The year before, Phillips argues, laid the groundwork for all that followed.

Consider how active events became in 1775. In Massachusetts alone, the British faced fierce opposition at two of the most important battles in the war: Lexington and Concord. Within days of those skirmishes, the English troops found themselves marching up Breed’s Hill (commonly misremembered as Bunker Hill). Just how important did this one battle in the summer of 1775 turn out to be? Phillips writes, “The number of British officers killed and wounded on June 17 represented a quarter of those officers killed and wounded during the entire Revolutionary War.”

Meanwhile, Congress was already meeting in Philadelphia and establishing crucial policies that would help