Why did comprehensive health care reform pass in 2010? Why did it take the form it did—a form that, while undeniably ambitious, was also more limited than many advocates wanted, than health policy precedents set abroad, and than the scale of the problems it tackled? And why was this legislation, despite its limits, the subject of such vigorous and sometimes vicious attacks? These are the questions I tackle in this essay, drawing not just on recent scholarship on American politics but also on the somewhat-improbable experience that I had as an active participant in this fierce and polarized debate. My conclusions have implications not only for how political scientists should understand what happened in 2009–10, but also for how they should understand American politics. In particular, the central puzzles raised by the health reform debate suggest why students of American politics should give public policy—what government does to shape people's lives—a more central place within their investigations. Political scientists often characterize politics as a game among undifferentiated competitors, played out largely through campaigns and elections, with policy treated mostly as an afterthought—at best, as a means of testing theories of electoral influence and legislative politics. The health care debate makes transparent the weaknesses of this approach. On a range of key matters at the core of the discipline—the role and influence of interest groups; the nature of partisan policy competition; the sources of elite polarization; the relationship between voters, activists, and elected officials; and more—the substance of public policy makes a big difference. Focusing on what government actually does has normative benefits, serving as a useful corrective to the tendency of political science to veer into discussions of matters deemed trivial by most of the world outside the academy. But more important, it has majoranalyticalpayoffs—and not merely for our understanding of the great health care debate of 2009–10.