Joel Isaac is Associate Professor of Social Thought at University of Chicago. His current research focuses on the relations between politics and economics in twentieth-century British and American thought. James Kloppenberg is Charles Warren Professor of American History at Harvard University, where he teaches European and American intellectual history. He has written several books on transatlantic politics and ideas from the 16th century to the present, including Toward Democracy: The Struggle for Self-Rule in European and American Thought. Michael O'Brien taught American intellectual and cultural history at the University of Cambridge. His research focused, in particular, on the intellectual history of the American South. Jennifer Ratner-Rosenhagen is Merle Curti Associate Professor of History at the University of Wisconsin-Madison. Her research focuses on 19th- and 20th-century US thought and culture in transatlantic perspective.