This is not a modest book. In its pages, I contend that the way that most in the field go about explaining international cooperation and the creation of international organizations, as the rational and functional response to objective security environments marked by uncertainty, is almost always too narrow, often obvious, and sometimes exactly wrong. Drawing on insights from social psychology, I contend that trust, rather than distrust, drives the institutionalization of cooperation and the construction of multilateral institutions. And the type of trust that matters, the “generalized” variety, is dispositional, an attribute of decision-makers that varies even in the same structural situation. This book is decidedly “old school,” seeking to provide better answers to old questions in the field – What explains international cooperation? Why do states create international organizations? – with new tools. In the course of writing this book, I have become convinced that some of the most foundational issues in international relations cannot be adequately addressed without attention to psychology. Like many, given our field's dispositions (and prejudices), I originally resisted its insights as reductionist and lacking external validity. I am now a convert. I hope to change readers’ minds as well, including those already drawn to psychology but who self-ghettoize themselves in the field of foreign policy analysis with the mistaken belief that international relations is somehow a bridge too far.

Writing a preface for a new book is tremendously gratifying, particularly as books are always the culmination of a long process and each has its own story. This book about American multilateralism actually has its roots in Europe. It began with an observation I made while an undergraduate study abroad student in Vienna observing the tortured ratification process of the Maastricht Treaty in Western Europe in 1992. Sitting in Vienna cafés reading the now-defunct European newspaper, I noticed that conservative parties in particular seemed to resist encroachments on national sovereignty, but I didn't know why.