The introduction provides an overview of the book, presents the core arguments, highlights the contribution to current literature, explains the book’s methods and sources, and outlines the structure of the book. The overarching argument of the book is that intelligence cooperation was so beneficial for all parties that European authorities therefore let Mossad carry out its operation and tolerated the use of its intelligence to kill Palestinians. Hence, the book demonstrates that the extensive advantages that European agencies gained through Club de Berne intelligence-sharing led them to turn a blind eye towards, or even tacitly support, Israeli covert actions on their respective territories.

This chapter develops the conceptual basis and theoretical framework for the study, relating to relevant literatures in intelligence studies, peace studies and constructivist theories in IR. It discusses normative versus analytical approaches to warnings in foreign affairs and explicates problematic assumptions in the literature. It argues that warnings come in various forms and may contain a variable mix of knowledge, relevance and action claims. They can differ greatly in their senders’ intentions and relationships to recipients. Therefore, warning impact needs to be measured in a more nuanced way than whether warnings led to effective preventive action. The chapter develops a theoretical framework that draws on the most relevant insights from literatures in social psychology, advocacy and political communication to explain when warnings are persuasive. It distinguishes between outside-in warnings from NGOs and news media and inside-up warnings through intelligence analysts and diplomats. The framework elaborates which variables can best account for differences in persuasive success and how they may interact.