Recent research has questioned the traditional assumption that populations inevitably rally round their national leaders in times of war and suggested instead that whether this occurs depends upon political communication and mass media coverage. In this study, we provide systematic analysis of the debate in Scotland over the invasion of Iraq in 2003. We examine how the conflict was construed as either for or against the national interest, and how the way this is done is linked to different dimensions of context. First, we provide a mixed-methods analysis of debates in the Scottish Parliament. We show that anti-war speakers from Scottish separatist parties map opposition to the war onto a series of collectively consistent and temporarily flexible categorical oppositions, starting with a familiar antinomy between Scottish people and British rulers (before the invasion), and then shifting to broader oppositions between subjugated people and imperial powers (after the invasion). By contrast, speakers from other parties appear less consistent and less flexible in the nature of their arguments. Second, we examine the opinions of a population sample on the war, how these opinions relate to understandings of Scottish identity and how the media context is pivotal in the translation of anti-war opinions into votes for separatist/anti-war political parties.