The Cuban Missile Crisis is by this point well known to all scholars of international politics. Yet, although it has yielded countless lessons over the years, one critical aspect of the case has remained unexamined: the failure of estimation prior to the crisis that led U.S. officials to discount the possibility of a missile deployment in Cuba. This article re-examines U.S. intelligence estimates of the Soviet Union prior to the Cuban Missile Crisis in light of the concept of ‘mirroring risk,’ introduced in this article. I present a framework for understanding a class of intelligence failures that are caused by the mis-assessment of how an adversary frames a decision and the risks that they are willing to take. I also present a new two-stage process for understanding how individuals assess the risk-propensity of adversaries in international politics.

How states assess the capabilities of their adversaries and rivals is of paramount importance to the theory and practice of international relations. This paper presents a framework for understanding why states overestimate the capabilities of their adversaries. Three types of overestimation are presented, consisting of conscious/rational, erroneous and biased overestimation. In order to demonstrate the phenomenon of biased overestimation in international politics, the case of the ‘Missile Gap’ (1957–61) controversy in the United States is examined.