What Is the Affordable Care Act a Case of? Understanding the ACA through the Comparative Method

International comparisons of US health care are common but mostly focus on comparing its performance to peers or asking why the United States remains so far from universal coverage. Here the authors ask how other comparative research could shed light on the unusual politics and structure of US health care and how the US experience could bring more to international conversations about health care and the welfare state. After introducing the concept of casing-asking what the Affordable Care Act (ACA) might be a case of-the authors discuss different "casings" of the ACA: complex legislation, path dependency, demos-constraining institutions, deep social cleavages, segmentalism, or the persistence of the welfare state. Each of these pictures of the ACA has strong support in the US-focused literature. Each also cases the ACA as part of a different experience shared with other countries, with different implications for how to analyze it and what we can learn from it. The final section discusses the implications for selecting cases that might shed light on the US experience and that make the United States look less exceptional and more tractable as an object of research.