Historians are the last isolationists in the United States; standard treatments of American history almost always fail to ground it in the global context. Economically, politically, culturally, intellectually, Americans have always been part of a wider world, and American history cannot be clearly understood until it is reintegrated into the history of the world. The first and most important task for ambitious historians out to reshape the traditional understanding of the American past is to come to terms with the immense role that the U.S.-British relationship played for so many years. The United Kingdom was the United States' most important trading partner, economic rival, political model, security threat, and source of ideas. Generation after generation of American politicians, merchants, investors, intellectuals, artists, political theorists, reformers, and religious figures were shaped by the similarities, differences, rivalries, and cooperative enterprises of the two great English-speaking societies, yet American historians have only rarely and intermittently addressed this great subject. Burk's Old World, New World is more than a good book; it points toward a new kind of history that is much needed. Nonetheless, the book is uneven; the sections on diplomatic history are often strong, sometimes brilliant, whereas the treatments of cultural and intellectual history generally disappoint. No matter; what Burk does well is important, and as she and others explore this great subject, they will produce a body of work that will both sharpen Americans' understanding of the nation's past and illuminate the challenges currently being faced.