Dramatic and unsettling events in the European Union’s (EU’s) external neighbourhood have underscored yet again the continuing relevance and analytical utility of realist international theory. Europe’s initial aspiration to surround itself with a ‘ring of friends’ and to export good governance, economic prosperity and stability to its neighbourhood by means of ‘soft power’ and normative inducements has not been realised. To the South, the so-called ‘Arab Spring’ has turned sour, and the continuing ramifications of the United States (US) invasion of Iraq in 2003 have led to the rapid spread of ISIS from a deeply fractured Iraq to war-ravaged Syria and Libya. The EU now faces an acute and growing threat to its security from state failure, regional conflicts and terrorism across the Middle East and North Africa. To the East, Russia’s annexation of Crimea and simmering conflict in eastern Ukraine have highlighted the deeply rooted structural obstacles to political transformation, inclusive governance, economic modernisation and social justice throughout much of the post-Soviet lands. Above all, the military assertiveness, territorial aggrandisement and recidivist aspirations of Russia have shattered the fundamental strategic assumptions upon which the post-Cold War European security order has been constructed: namely, that the EU’s Member States face no strategic challenges and that regional security competition has been largely tamed or muted.