Constitutional democracy is at once a flourishing idea filled with optimism and promise--and an enterprise fraught with limitations. Uncovering the reasons for this ambivalence, this book looks at the difficulties of constitutional democracy, and reexamines fundamental questions: What is constitutional democracy? When does it succeed or fail? Can constitutional democracies conduct war? Can they preserve their values and institutions while addressing new forms of global interdependence? The authors gathered here interrogate constitutional democracy's meaning in order to illuminate its future. The book examines key themes--the issues of constitutional failure; the problem of emergency power and whether constitutions should be suspended when emergencies arise; the dilemmas faced when constitutions provide and restrict executive power during wartime; and whether constitutions can adapt to such globalization challenges as immigration, religious resurgence, and nuclear arms proliferation. In addition to the editors, the contributors are Sotirios Barber, Joseph Bessette, Mark Brandon, Daniel Deudney, Christopher Eisgruber, James Fleming, William Harris II, Ran Hirschl, Gary Jacobsohn, Benjamin Kleinerman, Jan-Werner Müller, Kim Scheppele, Rogers Smith, Adrian Vermeule, and Mariah Zeisberg.