Balancing against threats or bandwagoning with power? Europe and the transatlantic relationship after the Cold War

The United States has played an important role in European security since the early 20^th century. From the time of the end of the Cold War, this role has changed as a consequence of the lack of a common territorial threat and the overwhelming power of the United States relative to Europe. How have European states responded to the challenges of the American world order? Are they adapting their security policies to match the challenges of US security policy and the American world order? What are the implications of the European response for the transatlantic relationship? This article seeks to describe and explain European security behaviour in the American world through the prism of two realist theories: balance of power realism and balance of threat realism. Despite sharing a common starting point in realist assumptions, each theory allows us to tell a different story about Europe's position in the American world order as well as the opportunities and challenges it faces.