Concern is rapidly growing about obesity rates in the United States. This paper analyzes the political consequences. Despite myths about individualism and self-reliance, the U.S. government has a long tradition of regulating ostensibly private behavior. We draw on the historical experience in four other private realms (alcohol, illegal drugs, tobacco, and sexuality) to identify seven "triggers" that prompt government to intervene in citizens' private habits. We suggest which of those triggers have been tripped--or are in play--in the case of obesity and food consumption. Finally, we review what government now does in this field and what it might do in the future.