When assessing worries about American empire, some historical perspective is helpful.  Jane Burbank and Frederick Cooper reminds us in Empires in World History: Power and the Politics of Difference that “Throughout history, most people have lived in political units that did not pretend to represent a single people.  Making state conform with nation is a recent phenomenon, neither fully carried out nor universally desired.”

Further, the process of turning an empire into a nation-state can be brutal: “In the 1990s the world witnessed attempts by political leaders to turn the state into an expression of ‘their’ nationality: in Yugoslavia - a country put together after World War I on terrain wrested out from the Ottoman and Habsburg empires - and in Rwanda, a former Belgian colony.  These efforts to create homogeneous nations led to slaughter of hundreds of thousands of people who had lived side by side.  In the Middle East, Sunnis, Shi’ites, Kurds, Palestinians, Jews and many others have fought over state authority and state boundaries for more than eighty years since the end of the Ottoman empire.  Even as people struggled for and welcomed the breakups of empires over the course of the twentieth century, conflicts over what a nation is and who belongs within it flared around the world.”