British Neutrality versus Offshore Balancing in the American Civil War: The English School Strikes Back

The American Civil War is an important test case for offensive realism because it was the last occasion when offshore balancing by Britain could have prevented the United States from becoming a regional hegemon. Instead, Britain drew on the norm of nonintervention to justify a policy of neutrality. Offensive realists reject the idea that Britain was constrained by normative considerations but disagree about why Britain failed to operate as an offshore balancer. I acknowledge the importance of the offensive realists' regionalized approach to the international system, but use English School thinking to argue that the normative framework that Britain and the United States subscribed to must be taken into account to provide a coherent explanation of Britain's response to the Civil War. Detailed archival research demonstrates that despite concern about u.s. regional hegemony, Britain was unequivocally constrained by normative considerations. The case study suggests, therefore, that societal constraints were stronger than systemic ones.