War in Ukraine in a polarised America

America’s response to the Russian invasion of Ukraine surprised many analysts, both because of its severity, and because of the speed and vigour with which it was implemented. Yet President Biden’s policy toward the war in Ukraine has also been noteworthy because of the bipartisan support it has enjoyed at home. Americans have become used to hyper-partisanship as a defining feature of their government and politics, but Biden’s policies of support for Ukraine have engendered a rare instance of cross-party unity in Washington, DC. For how long will US support for Ukraine endure? And what are the limits of bipartisanship? In this article, we argue that the key to answering these and related questions is to ascertain the national interests that US leaders view as being at stake in the war. After considering three rival explanations of US policy toward Ukraine, however, we conclude that it is difficult to determine whether there is any stable intersubjective understanding of the US interest in Ukrainian security. The future of America’s engagement in Ukraine will depend upon how the war is experienced, processed, and politicised by actors on the home front.