Twenty years after the NATO intervention in Kosovo, domestic Western societies seem to have become more distrustful of the possibility of invoking and implementing humanitarian intervention (HI). This paper focuses on the 2011–2015 British domestic debate on the possibility of using force against the Syrian Government of Bashar al-Assad and against the Islamic State in Syrian territory. The goal is to understand how relevant domestic actors, namely the Government and the political parties, debated the concept of HI and engaged in several discursive strategies with the goal of influencing the decision on whether or not to intervene. The perception of the Members of Parliament about the failure of previous British governments of different ideological affiliations to carry out successful and useful interventions, especially in Iraq and Libya, favoured the development of an ‘intersubjective understanding’ that reflects a more precarious consensus on HI. The paper explains how the historical analogies of operations Iraqi Freedom against Saddam Hussein and Unified Protector against Muammar Gaddafi shaped the perceptions of political parties by pushing them to claim a larger say in disputes related to the legitimacy and feasibility of these operations.