Introduction

When the Berlin Wall fell in 1989, triumphalists exulted in what seemed a double revolution: the arrival of the United States’ “unipolar moment,” and liberal democracy’s victory over its twentieth-century authoritarian ideological competitors, first fascism and then communism, in what was hailed as “the end of history.” ¹ These events were momentous, whether judged from the standpoint of either realism or liberalism, the two dominant paradigms used by both scholars and pundits for thinking about international affairs.