Book excerpt: Positing that presidents shape America's foreign policy according to their ethnic heritage, this intriguing volume examines two groups that have dominated the presidency and the distinctly different agendas that have resulted. How is American foreign policy determined? The Great Anglo-Celtic Divide in the History of American Foreign Relations approaches that question from a fascinating perspective, arguing that, to a large extent, the answer lies in the ethnicity of the president. To make its point, this book examines the key foreign policies of American presidents from George Washington to George W. Bush and shows how their most important foreign policy decisions have tended to follow an ethnic pattern. The presidency has been dominated by Americans from English or Celtic backgrounds since the nation's founding, and as readers will discover, the foreign policies of the two groups have been very different. To document those differences, this book analyzes seven alternating periods of political domination by Anglo-Americans and Celtic-Americans, demonstrating how the cycle of change affected the shape and distinguishing characteristics of U.S. foreign policy in matters of war and peace and in relations with other countries.