It is generally agreed that the central task of social and political philosophy is to provide a justification for coercive institutions. Coercive institutions range in size from the family to the nation-state and world organizations, like the United Nations, with their narrower and broader agendas for action. Yet essentially, they are institutions that at least sometimes employ force or the threat of force to control the behavior of their members to achieve either minimal or wide-ranging goals. To justify such coercive institutions, we need to show that the authorities within these institutions have a right to be obeyed and that their members have a corresponding duty to obey them. In other words, we need to show that these institutions have legitimate authority over their members.

In philosophical debate at the beginning of the twenty-first century, a number of competing justifications for coercive...