Abstract The war in Ukraine created a situation in which various actors issued and responded to existential threats. These incidents of aggressive rhetoric invite a scholarly discussion about the securitizing moves of deterrence. More specifically, I identify five interrelated securitizing moves—each responding to the other moves—within which deterrent threats are embedded: It allows us to trace how Russian enunciators securitized the threat from the West and Ukraine and justified taking the exceptional measures of an invasion. This resulted in Ukraine making a counter-securitizing move, with the aim to receive international military assistance. In addition, the Russians securitized a potential direct involvement of NATO in the war in order to deter it. Locked between these securitizing moves of Russia on the one hand and Ukraine on the other, NATO members eventually chose to advance an extended deterrence by denial strategy through the unique means of providing weapons. By delivering the message that they are committed to support Ukraine, they aim to convince the Russians that allocating resources to fight in Ukraine is a worthless endeavor. Examining this case thus offers interesting implications for both deterrence and securitization theories.