This paper focuses on the European Union’s reaction to the 2011 Libyan crisis as a case study. It seeks to demonstrate the limitations of the ‘strategic culture approach’ in observing and explaining the EU’s lack of a common response, which would have involved the development of the Common Security and Defence Policy (CSDP), and to demonstrate that the ‘domestic level approach’ has greater explanatory power. It lays emphasis on France, Britain, Italy and Germany as a sample of the EU/27. The empirical material includes several interviews.