Addressing the anti-mercenary norm, this article offers an original empirical contribution and a new theoretical framework, where taboo talks, hide-or-justify strategies, and inconsistent behavior define the robustness of a norm. I code and analyze all references to mercenaries and private military companies in the Italian and British parliamentary debates from 1805 to 2017, and I demonstrate that the norm evolves through three critical moments. Between 1805 and 1945, an anti-mercenary moral norm is present to a relevant extent in politicians' debates, though it does not consistently constrain states' behavior. The norm is weak. Between 1945 and 1991, anti-mercenary sentiments start to decline, and all discussions about their operations are clearly distorted by Cold War dynamics. The norm is very weak and highly politicized. After 1991, the norm targets security contractors for a brief period, as negative references and moral attacks significantly decrease. The norm disappears.
