This chapter analyses how deterrence has looked over time, from the Partiya Karkeren Kurdistane (PKK's) birth, formation, maturation and establishment, and evolved into the balance of resolve between Turkey and the PKK. It provides a discussion on what it takes to build a credible threat, which is worthy of addressing. The chapter reflects a process-tracing, which seeks to elucidate both Turkey's and the PKK's perspectives in a mutually inclusive fashion in each period as deterrence is a relational concept. As Turkey's fight against the PKK as Violent Non-state Actor (VNSA) indicates, however, the analyses on the "sole application of deterrence" in the literature is not fully sufficient to explain state-VNSA confrontations. VNSA confrontations, forgetting that the balance of resolve would first be the overall outcome after exceeding certain critical junctures and reaching a mutual military stalemate on the ground, and gradually, it would turn out to be a variable explaining outcomes.