Theories of Norm Strength and Erosion in International Relations

Why and how do international norms gain and lose strength? Depending on the underlying concepts and theoretical approaches, assessments of norm robustness in International Relations (IR) vary widely and have often led to competing conclusions. This chapter takes stock of the conceptual and theoretical debate on norm strength and norm erosion. It begins by discussing how IR scholarship has conceptualized norm robustness by focusing on different dimensions, including the legal character and institutionalization of norms, compliance and implementation, and concordance, which are often used in combination. Against this background, the chapter summarizes different and at times competing theoretical explanations for the strengthening and weakening of international norms, focusing on power and coercion, socialization and stigmatization, contestation and crisis, precedent and deviance, and institutionalization and legalization. Based on this review of the state of the art, the chapter outlines avenues for further theoretical and empirical research that combines explanatory factors and identifies scope conditions for turning points in the dynamics of norm robustness. The chapter concludes with an outlook for this section on norm robustness.