Transatlantic relations during the Bush administration sank to the lowest point in the post-war period following the invasion of Iraq in 2003. This article provides an analysis of both the current state of that relationship and the academic debate which accompanies it. Arguments over the impact of various factors are analysed to determine the extent of transatlantic divergence. Thus, demographic change in America and Europe, divergence of political values between Europe and America, power differences, post-war geopolitical realignments, European integration and American unilateralism and exceptionalism are all analysed and evaluated. While some of these arguments presented are challenged, the article argues that the process of constructing separate European and American identities from within the transatlantic community is the single most significant contemporary challenge to transatlantic relations.The active and public political opposition to the US-led war in Iraq by France and Germany in 2003 brought to an abrupt and dramatic end the post-war transatlantic bargain-that of American leadership and European deference in exchange for a military security guarantee in Europe and beyond. What was left was a divided alliance unsure how to relate to American power, or even what that power should be used for and directed against. Since the low point of 2003 there has been a concerted effort on both sides to mend relations across the Atlantic but there has been no return to the status quo ante. 1 What lay behind this particular crisis in transatlantic relations is an interesting case study of the current tensions in transatlantic relations and is the subject of this article. It is an assessment of the state of the debate as well as the extent of the damage caused by the disputes of the Bush era. Arguments over the impact of various factors are analysed to determine what is, and what is not, a structural driver of transatlantic divergence. Thus, demographic change in America and Europe, divergence of political values between Europe and America, power differences, post-war geopolitical realignments, European integration and American unilateralism and exceptionalism are all analysed and evaluated. While some of these arguments presented are challenged, the article argues that the process of constructing separate European and American identities from within what used to be the common transatlantic community is the single most significant challenge to transatlantic relations in the wake of the crisis over Iraq.Transatlantic relations have long been the subject of academic debate, with each successive episode being presented as uniquely different from the previous crisis in