This analysis investigates the role of historical analogies in the influence that parliaments have in foreign policy. Our empirical focus is the UK Parliament's unusual opposition to the Prime Minister on UK involvement in Syria in 2013. The vote challenges many conventional expectations about the role of parliament in security affairs. Important in this vote were lessons learned and strategically used from UK participation in the intervention of Iraq in 2003. This argument is developed theoretically based on research on historical analogies: parliaments, ‘learn’ (primarily negative) lessons about past foreign policy events which guide parliamentary preferences and procedures and can enhance parliaments' role in subsequent foreign policy. The article contributes to research on analogies by extending the logic to lessons on process. This use of precedents can offer more structurally oriented perspectives that translate critical junctures into reforms in procedures and policy-making practices.